I really can't endorse your brother-in-laws method of compulsion training especially with using the water. Also with the alpha roll over - that can backfire. Positive training does not mean all sweetness and treats either rather I consider it a way of teaching the dog that it is in his best interests to please me. I also use a combination of positive and natural dog training which uses the dog's prey drive to help me establish leadership and achieve cooperation.
Sting Chance von Gaard AKC GSD 2/8/2006