[jere]

I'm having a very hard time accepting the claims of original article, "The Physics Behind Traffic Jams."

Recently, I've tried to perform a few basic hypermiling techniques, especially "timing a light": if I'm the first car to encounter a red light, I leave extra space and can sometimes be moving through the light at 20mph or more when it turns green instead of stopped. It seems analogous to leaving space in front of you during a traffic jam, so that you can exit the jam at a faster speed.

The problem with this is that other drivers will often take advantage of your behavior. They think the most appropriate thing to do is race up to the red light. So instead of profiting from the faster speeds out of the light, they instead cut you off and start the light cycle at a predictable 0mph. You haven't done anything except swap places with these jerks.

[pertinhower]

...which also handsomely shows the real complexity of modeling systems where the human mind is involved, and the folly of over-simplified "1 car per 2 seconds" systems that look good in a computer model but fail to capture the real experience or decisions of piloting a car.

[losvedir]

Flying through a light that just turned green for you is a good way to hit a pedestrian or someone coming in from the left or right trying to catch the tail-end of their yellow.

Please don't do this.

[corin_]

Surely most (all) lights leave a significant gap between one set of people going red and the next going green. Of course, people noticing this gap may think "well it only went red two seconds ago, so I have time" - which would mean not shooting off at the green makes you safer - but if people get used to everyone else waiting 2 seconds after it turns green, then suddenly they have even more time after their turn goes red to make it through...

[cbr]

Vehicle sensing systems mean the basic assumption of light timing no longer holds: when you get to the light can affect how long you have to wait.

[jere]

I understand, but I'm not making the assumption. I'm talking about roads I drive everyday that are clearly on timers and I've even got good estimates on how long the cycles last.