What's wrong with undertaking? (not an enterprise, or the dead-body kind)

November 6, 2011 7:35 AM

Hot on the heels of this question, I've gotta ask you MetaFolks from outside the USA -- why do you have such a big problem with 'undertaking' ie passing in the slow lane?

For the sake of clarity, we're in a drive-on-the-right country, where you're only supposed to pass on the left. But why? Traffic slows down in the fast (left) lane; over here in the right lane, I'm supposed to slow down too? Why? Are you left lane drivers really going to blunder into my lane without looking, without signaling? And if you are driving safely, why is my passing you on the other side such an outrage? (Please, more to your answer than just "It's the law.")

posted by Rash to Travel & Transportation (43 answers total)

(Please, more to your answer than just "It's the law.")

But this is why. People are taught to drive in accordance with the laws and make their decisions on that basis. If somebody is driving against what the laws say, then their actions are less predictable for all the other drivers on the road, and more likely to cause accidents.

You could ask the same question about why everyone is so hung up on stopping at red lights. Are you really going to blunder into an intersection without looking? The whole point of having traffic laws is so everyone is on the same page.
posted by gerryblog at 7:39 AM on November 6, 2011 [28 favorites]

I thought it was because cars used to have a side-view mirror on the driver's side only, and between that and your peripheral vision, you'd see the car passing you much sooner and more easily is they came up on your left.

All the cars I grew up in (1970s, 80s) had mirrors on the left only (well, and the interior mirror).
posted by rtha at 7:40 AM on November 6, 2011

Simply put, it's confusing to get passed on both sides. If you're getting passed, it's your responsibility to scoot over to the right. It's enough to watch the crazy guy weaving behind you and the guy tailing you without having to deal with people passing you on the right. Additionally, right is generally your escape route in the event of something bad happening ahead of you, and you don't want someone speeding in that area.
posted by Gilbert at 7:45 AM on November 6, 2011

Merging into the middle lane to undertake at high speed risks a smash with someone legitimately merging into the middle lane from the slow lane to overtake, since neither driver will see the other in their mirrors. I think it's more of a problem in Europe, because we drive on average much faster on the motorways. It's considered perfectly normal for everyone in the fast lane to be cruising at 90mph+.
posted by roofus at 7:47 AM on November 6, 2011

Traffic slows down in the fast (left) lane; over here in the right lane, I'm supposed to slow down too?

I'm not sure, but my interpretation is that you don't have to slow down to match the left lane if it slows down, it's when you are switching a lane so as to overtake.

Ie you can be passing traffic in a lane to your left if the left lane has slowed - because that's not an overtake manoeuvre.

I may be very wrong. Any natives care to clarify?
posted by -harlequin- at 7:49 AM on November 6, 2011 [2 favorites]

Response by poster: Imagine a 3 lane highway.

I was under the impression these laws were only about classic autobahn-style two-lane limited-access roads. Note I'm in California where freeways can have four, five, even six lanes, where drivers are continually switching lanes (left and right) to avoid the slower drivers, and nobody's bothered by it, which seems perfectly normal and rational to me. And this driver doesn't require a side mirror on the other side (although it is handy) in order to monitor traffic over there.
posted by Rash at 7:51 AM on November 6, 2011 [2 favorites]

It's just as much about the law as it's about expectations. No matter in which traffic environment, you're depending on guessing what the next move of the other car is. Expectations about passing in the r-h lane match what the law says in this that or the other country.
Not observing that rule might go well a lot of times (also there's a soft transition between empty lane: no r-h passing, and full lane: every lane moves at its given speed, even if the r-h lane moves somewhat faster), but you just might bump into that one driver who didn't expect anyone to come and didn't look carefully in his right mirror before changing lanes.
posted by Namlit at 7:52 AM on November 6, 2011

That's my interpretation, -harlequin-. If the lane to your left has traffic that's slower than the one you're driving in, you can keep driving at the speed of traffic in your lane. But it's illegal to jump out of your lane in order to pass the person in front of you on the right.
posted by rtha at 7:53 AM on November 6, 2011

Oh and then, there's the rule (sometimes not observed, but still) which recommends driving on the r-h lane when you're slower. So ideally, the problem you're describing doesn't even occur.
posted by Namlit at 7:55 AM on November 6, 2011

It depends on the kind of passing on the right, not in terms of what's legal, but in terms of what's socially acceptable driving behavior.

For example, if there happens to be a painfully slow but self-deluding driver who refuses to move out of the left lane on a fairly empty stretch of four-lane Hwy 70, and if a string of faster-moving vehicles are quickly building up behind Grandpa and his combine, then most drivers, I believe, are okay with everyone in the queue passing on the right in an orderly, non-aggressive fashion.

But if, as is often the case, you have some douchebag in an enormous white truck with a spoiler and trucknutz tailgating you for six miles on a super busy six-lane stretch through downtown Indianapolis, who then violently pulls out into the right lane without looking to zip around you and everybody else, sometimes cutting across two lanes of traffic to make it to the next exit going at least 20 mph over the speed limit--well.
posted by daisystomper at 7:56 AM on November 6, 2011 [1 favorite]

I'm in the U.S. and I once had another car rear-end me on a two-lane highway because he tried to pass me on the right at the same time I changed lanes to let him pass in the left lane. Though in that case he was moving considerably faster than the speed limit. Fortunately he was able to brake enough that it resulted in nothing more than a mildly dented bumper.

Curiously, after I described the incident a friend of mine thought that if it had been a serious accident I would have been the one at fault, which I'm pretty sure is not the case, per not only the aforementioned laws but the fact that it was his car that struck mine.

Despite that experience I do pass people on the right myself but I slow down approximately to their speed when I do so.
posted by XMLicious at 8:04 AM on November 6, 2011

Visibility is worst in a car in the back corner opposite the driver. It's the blind spot, the place you have to turn your head to "shoulder check" to see if another car is there. It's easy for drivers to lose track of cars back and to their right (on a European or NA road).

Thus, undertaking, passing on the side away from the driver is dangerous because the overtaken driver may not be aware the passing car is there. This often startles the overtaken driver and greatly increases the stress of driving. Even "undertakeing" on multi-lane highways were passing on the right is somewhat expected stresses people out.
posted by bonehead at 8:10 AM on November 6, 2011 [3 favorites]

Uh, I'm a USian and I think it's often obnoxious when people are passing on the right. The point of traffic laws is not to impinge upon people's god-given right to drive wherever they want, it's to make driving patterns predictable and thus cut down on accidents.

Not that I never pass on the right. But I will follow for a bit on the left to give Mr Oblivious a chance to get over if they suddenly realize that maybe they shouldn't be going fifty in the fast lane.

Otoh, I just moved to a new city where people often pass on the right even if there's a lane to their left that is totally empty. That's just bad driving.
posted by geegollygosh at 8:13 AM on November 6, 2011 [1 favorite]

In Europe people are much more fastidious about keeping in the lane that is most appropriate to their speed. This has the consequence that a faster driver will almost always find it easier and more practical to overtake in the 'faster-lane' as there is probably a slower vehicle ahead in the slow lane that will get in the way.
posted by mary8nne at 8:20 AM on November 6, 2011 [1 favorite]

There is a definite accent to driving even within the USA, and when you get outside US borders it is a different language. US drivers often camp in the LH lane because it isn't torn up by trucks to the extent the RH one is, or because they're oblivious or foolish. To get around them you have to pass on the right. Yup, it's technically illegal in most of the USA. Yup, it happens all the time. There was an extremely weird situation in Georgia where trucks are (were?) forbidden the extreme LH lane on three-laned I-75 headed south from Atlanta. The fastest traffic was (speeding) trucks in the center lane. If the Georgia highway department hasn't fixed this yet, they're mad. On parts of I-5 in California, you'll get lines of cars in the LH lane passing slower trucks, and someone will shoot up the RH lane and then wedge itself into the line. That's followed by a ripple of braking from the whole LH lane's worth of traffic, thereby slowing down the passing ability of the whole line - in my view, situations like these mean someone is doing something very bad. If you don't think that's scary in itself, try it in fog - it's where a lot of chain-reaction wrecks come from.

In contrast, French drivers are much more apt to move to the right after a pass than US drivers are, and the flashing lights, honks, shaken fists and screaming out the window (I have seen all of them) tend to intimidate even the worst drivers into following suit. The autoroutes are generally much smoother than US roads and there is no disadvantage to moving right. That's not to say the French are paragons of driving. They do not bother anticipating and if you move to the left because you're going to pass a truck in the RH lane more than a hundred meters or so in front of you, you confuse everyone who's going to get within pissing distance of that truck before they lurch left.
posted by jet_silver at 8:21 AM on November 6, 2011

I think there should be an equal responsibility between those who want to drive slower and those who want to drive faster to share the road and help each other follow the law. I usually drive a little over the speed limit(try to keep it under 10mph over) and one of my biggest pet peeves is a person who is driving in the left lane and going either the speed limit or maybe a couple miles over it, seemingly oblivious to what is going on around them. If you are in the left lane and someone comes up behind you, MOVE OVER!

I see this all the time on I-95 where some slow poke thinks it's perfectly fine to hog the left lane and probably has set cruise control to the speed limit. These are people like my mother who say that people who speed are "criminals" and should be driving the speed limit. Fine, I'm a criminal, move your ass out of my way!

Huge pet peeve...my driving experience in Europe was different. I couldn't believe how much more willing to "work with" other drivers people in Europe seem to be. I've only driven in Germany and France, but it was great.
posted by fromageball at 8:29 AM on November 6, 2011

I'm with bonehead on this one: it carries additional risk thanks to reduced visibility on the rear passenger side, and because any movement sticks the bulk of the vehicle into the adjoining lane before the driver gets there. There are inherent risks to 'undertaking'; where laws prohibit it, they are intended to mitigate those risks, and in doing so create the collective assumption that it won't happen.

As mary8nne notes, lane discipline is a much bigger part of driver education in northern Europe, especially in Germany (in the UK, status anxiety stops people from driving in the 'slow' lane): not just with regard to speed, but in terms of thinking ahead and getting into the lane that's most appropriate for their eventual exit from a dual carriageway. That's difficult to map onto American interstate driving, where lanes will appear and disappear in haphazard fashion, along with exit-only lanes and left-lane exits.
posted by holgate at 8:29 AM on November 6, 2011 [1 favorite]

In contrast, French drivers are much more apt to move to the right after a pass than US drivers are,

A few years ago, I discovered that drivers in NM are much more likely to pass on the left, and then when they were done passing, to move back to the RH land; on my daily freeway commute here in CA, those who pass on the left tend to stay in that lane until their exit is near, or someone much speedier zooms up behind them.
posted by rtha at 8:34 AM on November 6, 2011

Most people (in every country) have their mirrors misadjusted and consequently passing on the right is dangerous.
posted by Confess, Fletch at 8:35 AM on November 6, 2011 [3 favorites]

There's a pretty large variation in speed between lorries doing 60 and Audi drivers doing 90. The distinction between the slow lane and the fast lane is intended to try and keep people driving at radically different speeds away from one another for safety reasons.

If Alice needs to overtake driver Bob it's clear that Alice is driving faster than Bob. Therefore it's unsafe for Alice to pass Bob by moving into a lane of traffic that's moving EVEN SLOWER than Bob. Not only might there be slow drivers and speed-limited drivers in that lane, but there may also be folks who have only just joined the motorway and who may only be doing 40 or so. Those people don't want to have to negotiate avoiding Alice who is driving at 75 in order to pass Bob.
posted by emilyw at 8:56 AM on November 6, 2011 [1 favorite]

Mod note: Folks, comments need to be answers to the question, not ranting about asshole drivers or things you hate about driving or traffic laws. Thank you.
posted by jessamyn (staff) at 9:03 AM on November 6, 2011

Flatly put, I always pass on the right. I live in areas where the number of idiot drivers is extremely high, and I can't think of a time this month when on a drive of at least 20 miles I didn't meet with an idiot driver stubbornly clinging to the far left hand lane while driving between 5-15 miles below the speed limit.

This happens with obnoxious frequency. I wish that we all would remember the driver's school mantra "keep right except to pass" because on the open highway, that's what I do. But driving is less courtesy and driver's education training these days than it is roller derby. I drive extremely defensively, looking for attempted "clotheslines" from drivers on their phones, feeding their kid, putting on their makeup, reading books (!), and I treat the entire freeway as part of my mission to get myself home alive.

And that means passing on the right at least once in every 20 mile drive.
posted by arnicae at 9:17 AM on November 6, 2011

Oh, hello, my fellow Californian! It sounds like you are going through the strange process I went through several years ago when I first started driving in a state other than CA. This is the process of learning that everyone in California drives like a total jerk. Again, I say that as a Californian. I had to re-learn how to drive, when I left, so that I could stop driving like a total jerk.

You identify one of the major reasons I point to, too. CA has such incredibly huge freeways, and it's easy to forget about passing rules when there are something like 7 lanes. Many of the freeways in CA are so crowded that rules about safe passing distances, etc, often are totally irrelevant. Furthermore, since everyone in California drives like a total asshole, it's hard to understand what driving is like if everyone doesn't drive like a total jerk. Only passing on the left makes no sense when you're the only one following those rules.

But, the thing is, if everyone follows the rules and doesn't pass on the right, this means that everything works more orderly. You can expect traffic to go slowest on the right and fastest on the left. You can stay in a slower lane except when you want to pass someone who's going slower than you. Since everyone else is doing this, it means it will generally be really easy for you to merge into the left lane, and then get back over once you've passed the slower vehicles. And no one ever gets stuck in a fast lane when they want to go slower than the people behind them, because people behind them will just wait for them to get back over to the right, rather than passing on the right. It's orderly, it's safer, and, in the end, everyone goes faster. No, I swear!

But, again, this only really works if everyone follows the pass-on-the-left rules. And no one in CA does. So, there's no real point to maintaining the pass-on-the-left rules in CA, since the whole driving culture is so crazy and messed up there. But, I promise you, it really does yield a saner, safer, and more enjoyable driving experience elsewhere.
posted by meese at 9:27 AM on November 6, 2011 [2 favorites]

Traffic studies have shown it's not the speed drivers are going but the differential in speeds that cause accidents. Unfortunately US police are more interested in ease of speed enforcement and the lucrative fines that follow than enforcing the reckless driving laws.
posted by Pecantree at 10:10 AM on November 6, 2011 [1 favorite]

bonehead hit the nail on the head...though i cant seem to get google to find the picture, there's one in every driver's ed book i've ever seen. the blind spot on the passenger side is much bigger than on the driver's side...if you pass on that side you are much less likely to be seen by the driver you are passing...i live in L.A. and drive like your grandmother...i ALWAYS check my blind spots before changing lanes...too many idiots on the road and getting home 5 minutes earlier is not enough reason, for me, to die in traffic.
posted by sexyrobot at 10:24 AM on November 6, 2011

California law explicitly allows (and actually encourages) passing on the right on any multilane roadway. Here's what the California Driver handbook says:

Pass traffic on the left. You may pass on the right only when:

An open highway is clearly marked for two or more lanes of travel in your direction.

So California drivers who pass on the right on freeways aren't "driving like jerks"--they're following the explicit rules of the State.

On a multilane freeway it would be utter chaos if everybody tried to crowd into the right hand lane "except when passing." The handbook (rightly) encourages people to pick a lane and stick to in (i.e, avoid weaving--which is the real asshole behavior on a busy freeway). That means that you inevitably end up in situations where your lane is going faster than the lane to the left.

In Europe, you're rarely driving on a more than two-lane road (e.g. Autobahn, autostrada etc). In those situations it makes perfect sense to have a "passing lane" and a "non passing lane." On a four or five lane freeway, it makes no sense at all.
posted by yoink at 10:34 AM on November 6, 2011 [1 favorite]

Because it's dangerous and stupid.

The reason we have the lane rules is to try to make the flow of traffic efficient. You want to go slowly? Go in this inside lane. You need to overtake the slow people? Move out one lane. You need to overtake the middling-speed people? Move into the fast lane. You're done? There's space in the slower lanes? Move back, so that faster people behind you are not impeded.

If everyone obeyed these rules, the traffic would flow well. So when you come across some... some... FUCKING INEXCUSABLE BASTARD hogging the middle lane while the slow lane is empty and people are stacked up behind him, you want him dead because he is wrecking the system. You want to do the right thing. You want to keep the traffic moving at the appropriate speed for the appropriate lane. But because of THIS INEXCUSABLE BASTARD you have a stack of people tailing him in the middle lane, you have people in the inside lane fretting (quite reasonably) that if they "undertake" him he is less likely to see them because he's sitting on the side of the car away from them - and, not incidentally, because people who follow the system reasonably expect to be able to move back into the slow lane without some frustrated person haring up on their inside and undertaking them. In other words, that reasonable expectation has become actually dangerous, because of the INEXCUSABLE BASTARD.

I'm frankly astonished this needs to be explicitly explained. It seems blindingly obvious to me.
posted by Decani at 11:06 AM on November 6, 2011 [4 favorites]

In Europe, you're rarely driving on a more than two-lane road

What? Have you been in Europe since the fifties?
posted by Decani at 11:07 AM on November 6, 2011 [3 favorites]

The main reason everyone should pass on the same side is to prevent drivers overtaking from opposite sides from colliding. This is particularly dangerous when overtaking a large, slow moving vehicles (e.g. a truck), because you have no visibility of the car passing on the opposite side before it's too late.

Additionally, right is generally your escape route in the event of something bad happening ahead of you, and you don't want someone speeding in that area.

Marginally related: Please don't do this - similar to how passing on the right is a bad idea, the driver on the right is counting on you not cutting in without warning.

If something bad happens, the right thing to do is try to keep control of the car and stop while staying in your lane. You are taking your chances that the driver following is keeping a proper distance and will not ram you from behind, but cutting to the right means you have a good chance to hit the car on the right and THEN be rammed from behind.
posted by Dr Dracator at 11:18 AM on November 6, 2011

yoink has a point about the megafreeways -- I've seen this in Atlanta, where you'll have six lanes each way, with lanes merging and going away, multi-lane feeder roads outside the main carriageway, and other craziness. With that, you just need to pick a lane and make smart choices about when to change lane in relation to traffic and your exit. Even then, I won't pass on the right, because I don't feel comfortable doing so.
posted by holgate at 11:37 AM on November 6, 2011

What? Have you been in Europe since the fifties?

I've driven extensively all over continental Europe (France, Germany, Austria, Italy, Spain, Hungary, Croatia, Greece, Turkey, Belgium, Netherlands, Poland--probably a few that I'm not thinking of off the top of my head), and most of those since 2000. Sure, there are the odd stretches of multi-lane roads, but nothing like as extensive as the freeway network in Southern California. There's a reason that Europeans like to sneer/marvel at LA's freeway system.
posted by yoink at 12:23 PM on November 6, 2011

I'm Australian, while it is frowned upon here to drive slowly in the right lane, we overtake on both sides and it is unremarkable.

When I went to live in the UK and Ireland I had to get overtaking on the left out of my system pretty quickly. I still fail to see how it's a big deal.
posted by deadwax at 12:24 PM on November 6, 2011

Even then, I won't pass on the right,

So if the lane to your left slows to a stop you just stop until it starts to move, regardless of what your lane is doing? Boy, you must hear a hell of a lot of tooting!
posted by yoink at 12:25 PM on November 6, 2011

Boy, you must hear a hell of a lot of tooting!

Nah. Sorry to disappoint you on that one. Like I said, I won't pass on my right, as in "go right, overtake, swing immediately back in leftwards". Too many variables, too many shitty drivers to second-guess, too much risk. I'll change lanes rightward if it's safe and sensible, but changing lanes isn't passing.
posted by holgate at 12:32 PM on November 6, 2011

You don't want pass on the right for a variety of reasons, chief of which are: because of the lack of visibility of the right, the other driver (especially a larger vehicle) might see you coming up on the rear and begin to change lanes to let you by. Meanwhile, you are already next to the vehicle and get run off the road. Second, if everyone is playing by the rules (HA!), the driver in the left lane is already passing someone. Third, drivers are taught to steer to the right when avoiding an obstacle in the road. Because again, if everyone is playing by the rules, a driver in the left lane knows whether there is someone in the right lane because he will have passed him. Fourth, since drivers almost always enter the roadway from the right, overtaking on the right could put you right into the path of someone entering the roadway.

Now, a lot of this goes out the window when you are in non-rural areas. There are too many entrances and exits, too many cars and they are all doing something different.
posted by gjc at 1:38 PM on November 6, 2011

UK here, the way I see it, if someone is oblivious enough to be going slowly in the fast lane, and the queue of cars building up behind them, then they're probably not going to notice when people start slipping down the "wrong" side of them to overtake.

But I agree with other people saying its just what you're used to, it just feels incredibly wrong to me to undertake (on the few occasions I've "had" to).
posted by chrispy108 at 2:17 PM on November 6, 2011

Response by poster: So if the lane to your left slows to a stop you just stop until it starts to move, regardless of what your lane is doing?

This was the situation I was in while driving with a friend in Switzerland, and I was baffled when she said she was breaking the law by NOT slowing down to match the speed in the "fast" (but now much slower) lane.

All this talk about blind spots takes me back to my original comment -- would a faster-lane driver (in that situation) actually blunder into my lane without looking, without signaling?

And thanks for pointing out the mirror thing, Confess, Fletch -- I've had my mirrors correct since becoming enlightned via a "Mechanics Illustrated" article from a long time ago, but most Americans adjust them wrong -- I think we're taught to do it that way in Drivers Ed.
posted by Rash at 3:50 PM on November 6, 2011

All this talk about blind spots takes me back to my original comment -- would a faster-lane driver (in that situation) actually blunder into my lane without looking, without signaling?

Yes. A lot. With alarming frequency.

/60-mile freeway commute
posted by rtha at 4:06 PM on November 6, 2011

Note I'm in California where freeways can have four, five, even six lanes, where drivers are continually switching lanes (left and right) to avoid the slower drivers, and nobody's bothered by it, which seems perfectly normal and rational to me.

Being in CA might be part of your perception. As others have mentioned, drivers in other states are (as far as I've noticed - I'm a CA native) much more likely to return to the right lane after passing a slower car by switching to the left lane. When I took a road trip earlier this year through Arizona and New Mexico, almost no one drove in the left lane unless passing (or they had CA plates).

Typically, the right lane moves a bit slower anyway, just because of traffic exiting and merging onto the freeway.
posted by LionIndex at 4:45 PM on November 6, 2011

I'm Australian, while it is frowned upon here to drive slowly in the right lane, we overtake on both sides and it is unremarkable.

Same in NZ.
What you'll find is that people are used to the traffic rules they grew up with, and find them to be Obviously Sensible [except when they aren't], and the rules of other counties are Insanely Dangerous.

For instance people from the UK will get very exercised about passing someone in the slow lane [so dangerous!], yet they think that reversing around a corner or parking on the wrong side of the road are perfectly normal and safe things to do.
posted by HiroProtagonist at 6:41 PM on November 6, 2011

USian who has driven a fair amount in Germany.

I felt far safer driving in Germany than I ever feel here in the US, because I knew with near-certainty what very other driver on the road would do. If I came up behind someone, they would move over as soon as possible to let me by. I someone came up behind me, they wouldn't gun it and swing around me on the right if I took a fraction of a second too long to let them by. You don't get self-appointed speed limit monitors sitting in the fast lane going 55.

It's all about the predictability of traffic, for me.
posted by chazlarson at 9:38 AM on November 7, 2011

I felt far safer driving in Germany than I ever feel here in the US, because I knew with near-certainty what very other driver on the road would do. If I came up behind someone, they would move over as soon as possible to let me by.

Yes indeed. Of course, that's because if you stay in the left lane in Germany and you're not passing you'll only have to wait about five minutes before you find you have a Porsche two inches from your bumper flashing his high beams at you to pull over. It's a pretty effective system for traffic behavior modification.
posted by yoink at 10:45 AM on November 7, 2011

Overtaking on the right when overtaking on the left is convention is just plain unsafe - and not just a matter of convention. Accident rates aren't a function of average speed, they're a function of standard deviation. Overtakers using the lane generally reserved for slower traffic results in an higher std dev in that lane. Bad things happen when both fastest and the slowest vehicles are using the same lane.
posted by klarck at 5:14 PM on November 7, 2011 [1 favorite]