You have hit many of the game management variables that there are. If a coach is starting to chirp from the dugout, nipping it in the bud is crucial. My SOP (I didn't invent it) is IAWE. I - Ignore the first belly-ache remark (unless it violates the 3-P's referenced above)...maybe that's all he'll say. A - Acknowledge what's happening ... I stare at the person, let him know, I know who's misbehaving...maybe he'll get it. W - Warn him "Knock it off" perhaps add "This is your warning for the game" E - If he has ignored your warning and continues to misbehave, he won't stop, so get rid of him. E for eject. Other coach-umpire situations arise on close plays the the coach may want to "discuss". 1. Don't argue with the coach ... answer pertinent questions that he has a right to ask. 2. Don't reply to statements. Sometimes coaches make false statement ... don't take the bait...don't argue. 3. Know the rules, Be able to concisely explain what and how a rule was violated. 4. Keep your statements as brief as possible, "in my judgment, the runner beat the tag" 5. Resist the urge to elaborate, it'll only prolong the "discussion" and may get you in more trouble. 6. Keep the discussion brief. After he's had his say, and you've explained your call, end the discussion and get back to baseball. 7. Practice ... rehearse the words at home/alone, so you'll be less likely to be tongue-tied when the pressure is on. We could write a book on coach-umpire "discussions" and game management. Above is really only scratching the surface of the topic. I'm sure others will add their own approaches ...dos/don'ts. You have to find what works for you.