Drive well, drive safe
I've witnessed no accident caused by speeding. I've seen near misses caused by (a) driving too close (b) distracted drivers (phones/food/fags/family) (c) sudden unpredictable driving changes (d) lack of indication (e) the slow lane creep of the drowsy/sleepers (f) idiotic maneuvers (g) lack of consideration to weather conditions.
I'll grant you that going faster reduces your ability to cope with other peoples mistakes, but a blanket limit is counter productive because wherever the driver feels it's unnecessary, it's disregarded and that reaction is easily extended to the point where there's no respect for the rule, in a place where it's actually extremely appropriate.
I've followed many drivers that stick to the 60 limit on the open road and then refuse to drop below 40 in 30 limits. I'd rather see 70+ mph on the open road (with care) than 40mph in a village/town, where vulnerable pedestrians are much more common and where road hazards abound.
Thrashing the bad boy when caught, does not enforce the rule, nor (more importantly) engender appropriate behavior in future. More often than not, it encourages worse behavior.
It does, however, tax the relationship between the individual and law makers/enforcers.
Teach better driving habits, not compliance and reward those that excel.