ZIPPER MERGING
Taking turns eases jams
Zipper merging will never happen until we have autonomous cars.
People just hate total strangers too much for common sense to ever get in the way. The physics of the merge — use all of two lanes until the last second, at which point a car from each lane should proceed in an orderly fashion — has been proven, repeatedly, to reduce congestion at crash sites and construction zones. It should be easy; you’ve only to look down at your own crotch to see how a zipper works, as well as understand the frustration when it doesn’t.
The Alberta Motor Association (AMA) recently posted a release about zipper merging. It has officially stated, like so many before, that merging is most effective when done at the last moment; those who speed down the emptying lane are doing it right, and you who pulled a Boy Scout and got all prepared as soon as you saw the signage, are doing it wrong. You are now the steaming Boy Scout, no doubt.
When the AMA report came out, media duly noted it, but nearly all proceeded to say why it would never work here, much as I just did in my opening sentence. We are hardwired to see those who cut to the front as cheaters, and even cheer on those who try to block them. It’s one thing if you think you are being a noble rule-follower, but could you finally be convinced you’re following the wrong rule?
Much as people will cling to a parking spot if they know someone is waiting for it (Ruback and Juieng, Journal of Applied Social Psychology), people will “hold” their position in a merging string of cars to punish the late intruder. That parking-spot study found if someone gets honked at, it makes the situation worse. Sounds about right.
Others will block late intruders — again, intruders who have science on their side — like so many Gladiators in Camrys. Maybe you get less stressed about all this, and just let in anyone because life’s too short. Maybe you make the judgment depending on the intruder; there is a remarkable bias against black BMWs driven by young males, and honking big pickups sporting Trucknuts driven by anyone. Or so I’ve heard.
To be clear, playing blocking games with your vehicles is dangerous, regardless of the situation. Yes, there are those who tear off down the shoulder and the sight of them being cut off by a rig can send a little shiver of schadenfreude down your spine. But using available lanes to do a late merge is not riding the shoulder.
If this were purely about physics or the law, it would work, because that would mean we were in Germany. They don’t mess around when they find a better way; they legislate it. They might be a little humourless, but they spend less time trapped in traffic than we do.
Municipalities could do better. If the goal is to encourage a healthy merge, there’s no need to post a warning sign five kilometres out. That just makes everyone — zippers, non-zippers, nervous drivers and black BMWs — start sizing up everyone around them. That’s five kilometres of unnecessary tension.
The New York Times reported a few months ago on a Colorado initiative that laid the groundwork for how to change motorists’ thinking. The first signs read, “Use both lanes during congestion.” The next signs said, “Use both lanes to the merge point.” When the lane was ending, the last signs read, “Take turns. Merge here.”
It’s simple, it’s clear, and it lets those doing it right not have to explain, and gives those dying to try it, permission.
Those yearning for the days of fully autonomous cars, of course, are giddy with the understanding that they will make this entire conversation moot. The cars themselves, those models of physics and reason, will merge like a zipper that’s been soaked in WD40.
Remove the human element, and you remove most of what is wrong on our roads.
The State of Missouri is testing a different approach. They’re simply defaulting to not providing too much information. Signage will indicate that a merge is coming ahead, but not which lane will actually be lost. Instead of providing too much information to drivers, who interpret it too many different ways, they give them just enough to be prepared for a merge. They’re getting complaints, but the bottom line is they’re reporting backup reductions of 50 to 75 per cent.
Perhaps this simple, uncluttered approach is best. Until the robots can take over, of course.