How about an opinion:

[mbyron]

Who said anything about training? That's a ridiculous red herring. Tee was asking about evaluation.

I and others have already explained the rationale for including coaches' input: they offer a perspective on an umpire's game management that nobody else can. Not a partner, not a paid or volunteer evaluator (who might not hear a conversation).

That's a small but significant component of an evaluation. It's certainly not intended as a substitute for an umpire doing an evaluation, which would cover far more ground and be the primary evaluative tool.

I'm not too surprised that many coaches would ignore opportunities to evaluate umpires. It's not required by their job, nor will it help them keep it. When you ask people to do volunteer work, you have to go out of your way to explain how it will benefit them, their team, and the game. Otherwise all you get are the cranks and hotheads (which could happen anyway).