[saalweachter]

You could do all sorts of technological enforcement of traffic laws.

You could have cars not permit going above the speed limit on highways for more than X minutes [to facilitate overtaking]. You could dynamically lower the speed limit during inclement weather. You could lower the speed limit when approaching an emergency vehicle by the side of the road. I'm not sure we have accurate enough position info to somehow force people out of the passing lane after a certain amount of time.

Hell, you don't even have to make it outright impossible to drive a car fast -- add a manual override switch, that removes the governor while logging your location and speed with the appropriate authorities. Audit after the fact to distinguish between "automatic speed limits were incorrect", "someone in the car was bleeding out on the way to the hospital" and "I wanted to go real fast".