re: Wait, so you can't block the plate in MLB?

You can't block the plate unless you have the ball.

The runner can't go for the head or initiate contact on the catcher unless the catcher (or anyone else covering home)blocks the plate.

Basically, you can't set up in front of the plate like in the past waiting for the ball. You must have the ball and then block.

It's done to let the catchers not seem like pussies when they don't want to stand in and take unnecessary shots when they wouldn't have been able to make a play anyway. It's a dangerous and vulnerable position to be in to be looking away from a 230 lbs. man bearing down on you trying to catch a ball.