Yeah, I completely disagree with no physical punishment. You should have to beat your dog, but in nature, the alpha does indeed use physical methods for behavior teaching.
A pop on the nose does wonders for teaching a young puppy.
One additional thing I would add to many of the steps above: Give and take food one a regular basis when they are young. This will pay off huge when your dog gets something it shouldn’t (something poisonous or maybe your neighbors cat) and you go to take it from him.
The food thing does wonders when introducing an adult canine.