I believe in his methods a 100%. The thing is he is not hurting the at all he is treating them the way that the pack leader would treat their pups in the wild. The leash pulling isn't pulling them to choke them he pulls it quick enough to grab their attention from what is giving them anxiety. He really does know what he's talking about.
Also the reason that he states that the dogs should be left on the floor (I don't do this because my little ones are to cute
) is because once you let a dog sleep on your bed and on the couch it makes them think that they are your equal or above you especially with larger breed dogs and yes yorkies too because they tend to be jealous. I do believe in the walking and holding them by the back of the neck it has worked for me since I have teld with overly aggressive dogs.
His methods are based on the health and well being of the dog from back in the day when dogs worked and doing what they were breed for and helping them extend their life. So many dogs are overweight, not sociaizedl, and overly hyper because they are not walked enough. Walking is huge for their life no matter what size they are.