This is all great advice. I have just acquired a lab/husky mix who has very aggressive habits towards chickens and cats. I think he would kill chickens; I don't know about cats. Anyway, he's about a year old and has clearly not worked with an "alpha" type person, which I am. He seems to learn well, and we are working on this all. Here's my question: what to do if I make a mistake in judgement and trust him too far? Or what if he gets let out by accident and kills a chicken? Just start over again? I don't believe in letting this happen, but it's possible it would.
Really, this isn't so unlike teaching children. Except children don't pull your arm off trying to get at the chickens. Usually.