Why do people assume that stopping the traffic all at once means that traffic is slowed down? Traffic in all directions has to stop at SOME point in the sequence. Just because there is always some traffic moving in some direction under the current system, we have the illusion that the inconvenience to pedestrians is made worth it because the traffic keeps moving. All-stop green crossings are quicker than the current system of stopping and starting pedestrians. You can have everyone over in 20 - 30 seconds max. So the overall amount of time traffic was held on a red would very likely be less.