[mbyron]

To answer an early question in this thread: when coach asks you "why can't he get help?" after you've told him that it's your partner's call (or yours, or whatever), tell him: "Coach, that's the two umpire system, and I don't have time to explain it to you right now. If you would like to read the manual, I can give you a reference after the game."

He might whine that it's not in the rulebook (which was likely where the original question was going anyway). You can tell him that there's a lot more to both umpiring and coaching than just knowing the rules.