Choke chain for a yorkie? I'm not quite sure about that. I recently enrolled my Tobi in puppy obedience classes, and I did a lot of research to find the right place for Tobi. Not ONCE throughout my research did I find a company that endorsed choke chain training for a puppy....they almost all claim to use positive enforcement (treats and praise).
I'm still a newbie when it comes to yorkies and training, but I would never make my Tobi endure choke chain training. I'm sure there are many MANY other places you can find that uses positive enforcement to train your pup. Good luck to you and Jolie!