Oprah Winfrey is not a reliable nor relevant authority on dog training. Or anything, for that matter. Wild Child, just because someone disagrees with you over a TV personality, you cannot then tell them "Well you haven't studied him enough," because it assumes everyone who has studied Cesar Milan 'enough' would have no disagreement about his methods. Which seems very, VERY far from plausible.
Here are some articles about relevant experts disagreeing with Cesar Milan and his methods:
I'm sorry but personal testimony is just not reliable evidence when it comes to assessing dog training techniques. There are also a few things you say that are incorrect:
"He never does anything to these dogs that naturally an alpha dog in a natural pack wouldn't do." - This assumes that an alpha dog, or the 'natural conduct' between animals, is beneficial for the animal. A lion kills its step children so the mother will enter heat and it can impregnate her. But I would not say that just because the step children are treated like this it is 'right' for us to treat them the same way.
"I doubt a tap in the side is going to do any serious damage." - Maybe not physically, but the controversy is over psychological damage. Which is, in the long term, quite serious.
In short, as vegans we see that animals should be given the same consideration as humans. If you had the job of rehabilitating a disobedient child, let's say he was severely down syndrome (this rules out being able to reason with him), would you use these same techniques on this child? Take some of your words and apply them to humans, i.e. "I would never endorse it if I thought was cruel or abusive. He is not booting into the 'kids' with aggression." "He had rehabilitated hundreds of fearful aggressive 'kids' to be balanced submissive 'kids'. Nothing has worked better with my 'kids' than Cesars techniques and my 'kids' are not afraid of me either, they are merely balanced 'kids' who know who their leader is.
Is your 'kid' a balanced 'kid' with no issues?"
Now the intention is not to imply that you would condone or even use these techniques on children (let alone severely down syndrome children), merely to show that the exact same argument you give here can be used to defend such practices.