Jerky Merging

I‘m done with school for the year, and so, also with my exciting four-hour commute up to Connecticut. Especially after the thaw, that already painful commute got further complicated with lane closures as they tried to repair the damage of Father Winter.

When a lane closes, the remaining lanes move slower. It’s that simple. People follow the instruction to merge (to the left or to the right) well in advance of the last possible point of merging, and as a result, the lane that is about to disappear always moves faster. And as a driver, you are faced with the ethical decision of when to move over. How many cars can you pass and still feel good about moving over? Or should you move over at the earliest possible moment, and sit in traffic as others race past?

It’s a classic ethical decision. I was, initially, of the “early mover over” camp, but then I realized that was dumb. Yes, taking advantage by cutting in on people who are in a queue is rude, but this is not a formal rule of the road, it is simply a warning: slow down and prepare to merge. Some people see that as “merge immediately,” some as “merge when required by the cones,” and most somewhere in between. I thought it was a good idea for the flow of traffic to start to move over, thus reducing the speed drop of forced merges. But there will always be “late mergers” and as a result, it’s stupid to leave all that asphalt unused. Seriously: why on earth do we think that increasing the total length of the lane restriction is a good thing?

Not surprisingly, this has been relatively well-studied, with much of the literature focussed on the type of merge to set up. In relatively sparse conditions, a nice long merge is a good idea. With more congestion, a late merge is smarter (again, since it uses up more of the road). The major problem here seems to be aggravated drivers at the merge point. Since I’ve crossed over from “early merger” to “late merger,” I’ve encountered these drivers. Pissed at having waited their turn while I zoomed up in an empty lane, they refuse to allow me to merge. Usually, the next person (or, ironically, the person ahead of them) waves me in. I understand their frustration–I used to be there, though I never would have aggressively tried to close the space so someone couldn’t merge.

Those who refuse to make space for a merge are the real problem, not the people who are zooming past in the soon-to-be-closed lane. By slamming on the accelerator and brake to make sure there are only inches between their car and the one in front, they set up the preconditions for fender-benders that then lead to extreme delays for everyone. The question now is how–short of leafleting the lane as I pass–is how to educate early-mergers to see the light and use the road?

Update: Thanks to Chutry’s comment below, I dug into Traffic author Tom Vanderbilt’s blog. He links to an article in the Oregonian that talks about the anger some people have over late merging (or should we call it “checkpoint merging,” as suggested in the comments over there).

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  1. chutry
    Posted 5/14/2010 at 8:00 am | Permalink

    I learned to embrace the late merge after reading Tom Vanderbilt’s book, Traffic. If the road capacity is there, why not use it?

  2. Posted 5/14/2010 at 9:02 pm | Permalink

    Another option you’ve missed is to slow down in the empty lane until you are moving at exactly the same speed as the care next to you, even if they are stopped and even if you have plenty of room ahead of you. Then, observe the following occur. First, the person immediately behind you rides your ass and scowls: how dare you keep her from flying by all these slow people! She deserves it and they’re just suckers! Then, as she realizes the only ways out of this situation are to either a) pass you on the median illegally (which, actually, one guy did to me), or b) just merge in at speed with the rest of the traffic, she begrudgingly merges in. The result of this is that merging happens much sooner before the crisis moment at the cones, and traffic actually frees up noticeably (ie, we all move a little faster).

    Once the person in the lane next to you realizes what you’re doing, you can just merge in front of him/her as you reach the cones with much less tension (and growing sense of injustice) for all.

    Try it some time and let us know how it works out.

  3. alex
    Posted 5/14/2010 at 9:46 pm | Permalink

    While that is an option, I’m not sure what purpose it serves. Here’s a typical situation on the 2-lane Merritt Parkway. They’ve closed a lane–let’s say the slow lane–for a period of about 50 yards in order to clear a fallen tree on the shoulder. Naturally, the left lane backs up, with people slowing down from the typical 70 MPH to 25 or so for safety reasons, and then the ripple effect that results in cars stop-and-go, bumper-to-bumber, for about a mile or so. Meanwhile, the right lane continues to move at about 25-30MPH–just fast enough to brake if someone decides to make a sudden move into the right lane.

    In these conditions, if I slow down to the left-lane’s speed, which in many cases is zero, I can understand why the person behind me might be aggravated. I generally spend enough hours on the road that I might become annoyed, but it doesn’t rise beyond my general annoyance of having to be driving anyway. But the person behind me who may, for example, want to take a right-hand exit up ahead, or who just wants to make use of a two-lane highway when there is a two-lane highway, is likely to be upset.

    Again, by doing this, I’ve halved the carrying capacity of the mile of congested road. This strikes me as irrational. It might make sense in the case where, say, the left lane is going 20 MPH, but when it’s completely stop & go, I’m just making the situation worse for the bright people who are choosing the late merge.

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