I agree with TexBlue. It's gonna happen no matter if you use perfect mechanics or not. I had an umpire in my area here who worked for like 30 years and claims he never got hit by a ball while working the plate. Of course, he also claims at the height of his career he worked 600 games a year.

I've seen the best here in Omaha/Council Bluffs get hit by balls that don't get caught by the catcher, and also have close calls with foul balls that "roll" back in the air at them. Bad mechanics? No, laws of gravity and nature. Just can't help it sometimes.