Read the
American Veterinary Society of Animal Behavior - AVSAB - Home statement. Googled a little on the org itself, and it appears to be well-respected. You may not agree with its conclusions, but this is not just a crackpoint-dogs should have the right to vote-type organization.
A a lay person reading the article, I am confused by some points. First, it says that scavenger dogs should be a better model for dog behavior - but when dogs play, they are clearly practicing hunting, and play behaviors, like grabbing a toy and not letting do, are the same behaviors that would tear an animals throat out.
Also, with the alpha roll - adult dogs DO roll puppies, so I'm not convinced it has no merit. If nothing else, it's an uncomfortable position for the dog, and could be used as a punishment.