Judging a persons driving purely on the speed that they are driving, without taking any other factors into consideration is ridiculous.
Sometimes its safe to exceed the speed limit, other times its not safe to be doing speeds anything like approaching it.
The current obsession with enforcing speed limits (as a cash generator,) encourages drivers to concentrate more on the speedometer, than the road.
I've got no sympathy for those who speed inappropriately and get punished (even though in the past I'll admit to doing it myself) but to condemn a person just for exceeding an arbitrary limit which is constant 24hrs a day regardless of road conditions, is short sighted in the least.
These days a lot of our attention, that should be spent observing the road, is instead spent constant checking the speedometer, in case we happen to have drifted slightly over the limit.
Couple that with the other (unnecessary) observations needed these days to be aware of fixed and mobile camera sites , then its amazing that we find any time to actually concentrate on the task in hand, namely driving in a safe manner.