You are seeing him deal with VERY problematic dogs, dogs on the verge of being put down often, because of their behavior problems, not based on any one breed, but on the dog's behavior. Breed has nothing to do with it, there are problems in all breeds of dogs with all types of people. He is not working with the "average dog" of whatever breed.
I am not basing it on Belgians -- I am basing it on Belgians with working sharpness. Belgians with working sharpness ARE put to sleep daily. If my dog ever shows any tendency to bite, I don't care if I have to use negative tactics to remove it. My dog was sharp her first two years I did not have her when she was only postitvely trained. An agility trainer told my cobreeder to put her down. Anyone here who has met Visa can attest to her very nice temperament. She is still drivey but she is no longer sharp. She is controlled. Solo I nipped right in the bud. And yes, I used negative training. But when it comes to biting, I really don't care.