[rcthompson]

Space clears out when traffic upstream starts to move. If the next traffic light upstream is synced to the current one, then space will consistently open up at the same point in the cycle, favoring whichever direction has the green at that point. If the lights are almost but not quite synced, then the "favored direction" will gradually cycle around the intersection over time.

> circle around

This is generally not possible, especially for the kind of intersections that have this problem. There generally is not a short path that would allow you to circle around, and even if there is, it's guaranteed to be completely congested by everyone else trying the same trick.