The merging solution is oversimplified. Leaving enough space for another car in front of you sounds easy. But in reality, if 1,000 cars each add 2 car lengths i

The merging solution is oversimplified. Leaving enough space for another car in front of you sounds easy. But in reality, if 1,000 cars each add 2 car lengths in front of them you've added 40,000 feet to the length of the slow down. Yep, 7.5 miles. If it was feasible, we could also stop at red lights with 3 or 4 car lengths between each car and when the light turned green everyone could go at the same time. There isn't space on the road for this type of behavior.