I believe umps have a responsibility to know all of the rules, no doubt. But I also believe that the assessment of your ability to be a quality umpire doesn't hinge on your ability to call every infraction in a game. Case in point; way too many umps are calling a balk in the following scenario:
pitcher removes ball from the mitt, prior to getting signs, WHILE engaged with the rubber, and is not remotely looking to put out a baserunner. I see this all the time. He is not attempting to deceive the runner, he is merely trying to get his balance and focus. Many times the batter is not in the box, yet.
Is he engaged? YES
Is he getting an unfair advantage by putting the ball in his hand after taking a step to the front of the rubber? NO
Mention the mechanics to the coach, so he can change it. This includes getting the signs before engaging the rubber.
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