I've also seen some pretty poor umping mechanics behind the plate at state over the years.
A few years ago I saw a guy that was calling a game with a D-1 bound pitcher that was touching 92-93. The ump blinked everytime a fastball came down the pipe. Tough to call a pitch when your eyes are closed, even if just for an instant.
My second pet peeve are umps who call the pitch before it crosses the plate; where they anticipate the outcome before they actually see the result of the pitch and then make the call.
In a championship game a few years ago, the ump was consistently calling a strike on a spiked curve ball when it was still 10 feet in front of the plate. The pitch ended up in the dirt in the left batter's box at a short 60 ft. He punched out the last two guys of the game on balls that didn't come close to touching the zone - let alone pass within reach of the batter. Kudos to the pitcher/catcher for gaming this umps bad habit.