I only read the first couple of posts, so forgive me if this seems off topic. lol
When properly used, I don't see why you can't use a choke chain. I train Blackie with one. But I also praise him and give him treats when he does what I want him to do. I basically use the choke chain to reinforce the commands he knows, but doesn't do when I tell him to. Like if I say sit, and he just looks at me blankly even though he knows this command perfectly, I'll give him a correction. When he sits, I praise him.
I would NEVER use a Choke Chain to stop a dog from pulling. That is dangerous. They aren't meant for that. I recentally got Rose a harness. It isn't a "No pull" harness, but it lets me control her so much better, so unstead of yanking her back every few steps (I can't do the stop and wait thing because I walk both dogs at the same time) I can just hold her by my side without choking her (she wears a normal collar) and then I just praise her when she isn't straining on the lead. She has picked up really quickly.
When I correct a dog, it is fast, firm, and fair. If the dog doesn't know a command and I tell it to him, would I correct? Heck no. I'd show him what I want him to do, then praise him when he complies. If you correct a dog when he doesn't know what he is supposed to be doing in the first place, it won't do anything.
You also have to correct the dog, exactly when he starts to do the bad behavior. If I'm doing a down stay with Blackie and gets up, I correct him as soon as I see him move to get up. When we walk by another dog, I don't correct Blackie when he starts growling and lunging at the dog, I correct him when he looks at the dog, and I give him yummy treats when he pays no attention to the dog. (He has gotten much better with other dogs now.) Just like when you "click" the clicker it has to be exactly what you want, you have to correct exactly when the behavior starts. You can't wait for the full throttle behavior.
I also think that on sinsitive dogs, you shouldn't be correcting very hard, if at all. Same with fear driven dogs.
Oh, and also, when you correct a dog, you shouldn't be jerking him around. You snap sideways, and as soon as you hear the chain tighten and fell the impact, you loosing emediatly. The dog shouldn't be moved by the force of the chain.
Personally, I like a mix of the meathods. I praise and treat and lure and reward to teach a dog something, but I'll correct the dog if he does something I don't like that he knows he isn't supposed to do. It draws a line, IMO. "If I stay on the right side and do these things, I get treats and praise, and lots of other things. If I go to the left side and do these things, I get a verbal, "No." and a leash jerk. Guess I'll just stay on the right side."
(Holy cow that was a long post...lol)