How long do you keep your sessions so the dog doesn't get desinterested?
With young dogs or older dogs new to it, the key is to keep it short. Watch your dog and try to quit before they become bored. You want it to be fun at this point.
I also do RallyObedience with Bogart and that's his forte so to speak. He really likes it. But I also like to try new things with him.
Also how do you teach the sit whistle stop or how ever you call it and the come whistle? I would love to teach him that.
I just start adding it to the command. We work on sit. When he knows that, I start blowing the whistle when saying sit. Keep at it and eventually you can blow the whistle by itself and he will know it means sit.
Same with the come in whistle. Sit him away from you, call him and blow the whistle.