@wewbull @Syldon
If by speeding you mean 35 in a 30 zone, then will the drivers who know their journey is urgent and important, as are try, and that they are more skillful than those around them, drive 15mph above the limit, or 5mph?
They'll stand out rather more if the former, and have a likelihood of killing a hit pedestrian or cyclist reduced by the change if the latter.
I suspect the chap recently apprehended for 61 in a 30 zone past children might not change, yes.
@wewbull
That's categorical thought, which is an error with a continuous variable such as speed.
That they break, or do not break, the law ("rule" doesn't quite describe it).
You may also care to consider that if one driver does not exceed the limit, it moderates the speed of others behind - you've presented this as an individual decision, uninfluenced by others, but even taken as a guideline others have influence.