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Josh Levine's avatar

I think it is a mistake to combine the two cases of "either merging or taking a turn".

If there is an upcoming turn and you can only turn from the inside lane and that lane backs up because, say, there is a light after the turn, then I think late merging can be anti-social and end up slower for everyone. A person who continues on in the through-lane eventually reaches the turn since no slots can open up while cars are stopped waiting for the light to change. He does not want to go past his turn so he stops to wait for a slot to open when the light turns. Now through traffic in the outside lane starts backing up so that not only are people who do not plan to take the turn unduely delayed, so are even the people who are going to take the turn since they are now stuck behind the non-turmers. The net result is that the traffic light now becomes a bottleneck for everyone. When people merge early, the bandwidth of the turn is used efficiently and reaches an equilibrium of some stable queue length before the turn, but when even a small number of people wait too long to merge then fewer people are able to make it through the light on each cycle and so the delay is longer for all groups (early mergers, late mergers, and especially through-drivers). This is a common case in NYC, and famously happens at the turnoff from the FDR drive to the Brooklyn Bridge.

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Richard Kain's avatar

A proper Übermensch does not obey (and cite) bureaucrats in midwestern departments of transportation. The Übermensch takes option 3: the otherwise closed lane lesser mortals fear to tread upon. Otherwise, why not go ahead and put on an N95 mask in the car?

The social cohesion and trust of said ethnically-similar states may allow for zippering but...lol I can't keep this up. Great article, your blog is the best

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