Just wanted to point out the obvious since it doesn't look like anybody has mentioned this...

Regarding skidding, California vehicle code requires a bicycle be equipped with a brake capable of locking a tire on flat, dry, level pavement. Pennsylvania might have a similar requirement, I'm not sure. As has been mentioned above, locking the tire up is not the most efficient way to stop your bike, but knowing where that point is and braking just before that (threshold braking) is the most efficient way to stop.