"On his TV show, the main method Millan uses for aggression is aversives (leash jerks, kicks, snaps of the hand against the neck, and restraint, among others) applied non contingently. The aversives are non contingent because they are so frequent that they're not connected to any particular behavior on the part of the dog—the dog gets popped pretty much constantly. This results in a state called learned helplessness, which means the animal hunkers down and tries to do as little as possible. This is what Millan calls "calm submission." It's exactly the same thing you see in a rat in a Skinner box that is subjected to intermittent shocks it can do nothing to avoid. This can happen quite fast, by the way, shall we say in ten minutes? The dangers to the dog are obvious, ranging from chronic stress to exacerbating the aggression, i.e., some dogs fight back when attacked. This latter is the simplest reason that aversives are a bad idea in treating aggression. Even used technically correctly as positive punishment for specific behaviors like growling and snarling, aversives do nothing to change the underlying fear or hostility, so the best you can hope for, in the words of famed vet and behaviorist, Ian Dunbar, is "removing the ticker from the time bomb." Thus such methods substantially increase the risk to humans of getting bitten."

Janis Bradley, Instructor at The San Franciso SPCA Academy for Dog Trainers
Author of the book, "Dogs Bite"