I'm wondering how you would know when the yellow light was going to come on.
Do you have some sort of countdown, or innate knowledge?
Because, otherwise do you just randomly stop at green lights guessing that a yellow light might come on? Or do you drive so slowly that you can stop in the width of the white line before a pedestrian crossing? Really, I'm trying to figure out how you don't ever enter just as a light turns yellow. Once you do, do you stop in the intersection or try to clear it before it turns red? I hope the latter.
For me yellow lights are a warning that a red light is coming. It should be long enough for cars to clear the intersection (in many states without gridlock rules even this is not the case for left hand turns).
My experience in Boston is that drivers try to beat the green light change and accelerate while it's still red.