Been there Phil. Ask anyone who's won an American Field event... they'll say the same thing. If your dog needs to be told not to move, he's not a steady dog.

I bring up NAVHDA on a rainy day because often times bobwhites will be used. Rain and bobwhites are a great test to the steadiness of a dog. I've seen handlers literally crawl on the ground looking for the wet quail. I've seen the same handlers throw the birds in the air, but they weren't thrown high enough to be shot. So, the handler needs to get the bird again, and throw it in the air (hopefully high enough to present a safe shot); all the while the dog is required to stay still without interference from the handler.

If you get your dog to this point, I think you'll see that getting him to flush on command will not effect anything.