I've always used a breakstick.....but hunted with a few that used the same pull up on the collar method as Mike said and that seemed to work great as well. Could never understand why some would smack their dog with a flashlight or fist to break them off.........They teach their dog to catch and then in a split second punish it for doing what it was taught.....I dont believe any good catch dog should have the "lightswitch" speed to turn on and off with a verbal command......and at the same time shouldn't be struck to let go of what he is suppose to be caught on......
just my 2 cents.....
Let me know, and I'll show you the baddest catchdog you've ever seen that was trained that way(my mentor's, which happens to be a cur, the father of my current stock). There's no "rule" that says one can't have an "educated" catch dog.... no break stick required.
An intelligent or shall we say, a "learned" dog
will do what you ask them to do. I prefer to work "with" my dogs rather than "against" them(which is what I feel a break stick accomplishes).
Why work against an animal when you can train the animal to work for you?