No one should be blaming an umpire for actually enforcing the rules of the game. The question here is whether the call was warranted and the rule was properly applied, not whether the ump is trying to show off to his other ump buddies.
Come on o2.
Is there any rule that says that your delivery has to be identical every time though? There shouldn't be anything wrong with making your delivery a bit quicker as long as there's no illegal move being performed or stopping in the middle of the windup.