I'm a bit nay and a bit yeah - but that's from the perspective of watching lots of animal shows, whilst only ever having been owned by cats.
I can understand (especially from reading topics here) that the "pack theory" and "dominance theory" make no sense, and if practiced to an extreme are harmful. A bit like the typical Victorian/authoritative father-figure, where the children (and usually the wife as well) would have to do as they're told. And that's not healthy.
There are a couple of bits of his shows, though, that do seem to make sense. One of them is when a dog rushes to the door when the bell rings. That's not a good idea, especially if the dog is a bolter. When he just stands there and patiently waits for the dog to get the hint to move back, that does make sense. I guess he'd call that showing "calm, assertive energy" but I think that it's the dog being given time to figure it out for itself.
As for dogs having to be fed last - good grief, that's nasty. Surely everyone knows that dogs have a superior sense of smell, so they'd be able to smell food being prepared long before the rest of the family.
I think that what he's actually done best is to get the message across to the dog owners who don't have a clue, that dogs need exercise and consistency. I gave up watching his show, because it was the same thing, time and again, and I felt like shouting at the TV: look, just take the dog for a walk, every day; and don't send mixed messages.
So, if he's managed to get across to his TV audience that dogs need exercise and fun every day, then he might have got some couch potatoes off their butts and taking better care of their dogs.