Originally Posted by akaJenT
I think they understand being flipped on their backs and growled at when they misbehave. It's what commonly happens in nature, they easily understand it and remember it and it doesn't hurt them in the slightest.
To a certain extent, yes, but what you do to flip a dog probably involves your hands and at the same time neglects certain aspects of a natural competition between two dogs. A second problem is that if you challenge your dog and LOSE, you have just proven HE's boss, not you! There are a lot of reasons you might lose, size of dog, speed of reaction, agility, mobility, length of muzzle, instinct, and the fact that he has been practicing doglike behaviours every moment since he was born.
Dogs - with the possible exception of those hand-raised since birth - do know the difference between a dog and a human, and are capable of responding to human behaviours and learning our language (body and vocal).
There are certain advantages to being human that can be used to trigger natural reactions in a dog. Height for instance: when your dog is on the floor and you are standing up your dog sees this as an expression of dominance on your behalf. Grabbing a dog's muzzle with your hand and applying light pressure and restraint - NOT grabbing it with your mouth in order to simulate the exact behaviour of another dog. Meal-feeding or nothing-in-life-is-free feeding. The use of personal space - walking into your tog to get him to back off accompanied by you talking in a growly voice - all done with your face safely higher than him (caution with some dogs on this, which you will know from the initial evaluation). And there are many others.
To me, the best way to express dominance and leadership to your dog is usually by combining an understanding of his natural behaviour and instincts with your natural abilities and advantages, rather than by getting down with him and pretending to be a dog, which he knows and understands you are not.