Most blocks don't happen in a 1v1 situation. If you watch Dwight Howard or some other good shot blockers, whenever someone drives past their defender they move over from help side wait for the shooter to leave his feet and then time their jump right and block the shot. It's all about timing. Look at all LeBron's chasedown blocks on the fastbreak, the player doesn't know he's there, he times his jump right and gets the block. And contest all jump shots, anytime someone shoots if you stick your hand out and contest the shot, without fouling, you'll get some unexpected blocks.

You need quick hands for steals. You have to be able to read the game. Whether it be guarding a man 1v1 or reading passing lanes, you have to be able to anticipate what's going to happen before it even happens. Watching an opponents eyes might help you read where they're going to pass it. Always have active hands defensively; and whenever the man you're guarding makes a mistake and gives you an opportunity to steal the ball, take it.