Dogs have a reason that they're biting. They don't bite for no reason. So, I would try to assess what is causing the dog to feel the need to bite. There are many reasons for a dog to bite. It most often is a defense mechanism. They're untrusting of something or someone. Some dogs bite because they've become too dominant, but my belief is that they are few and that reason is not as common. Some dogs bite because they're playing roughly. Some are teething and their gums hurt. Some bite to protect their food or possession because they think someone is going to take it. Again, a defensive bite. For treating aggression, you never use aggression as a means.
If Wrigley ever tries to bite (and he has never bitten out of agression more like play biting) I pick him up by the scruff and sternly tell him no--I put him down give him a toy he is allowed to chew on and ignore him.
Here, it is described as play biting. And you certainly don't use aggression to teach a pup who has not been taught how to have a soft mouth and bite inhibition. They need to be
taught. It is my belief that since we are humans and not dogs, we cannot emulate a mother dog or littermate closely enough to use this often misconstrued dog-like way of teaching. Mother dogs do not get that rough anyhow and it's few and far between that they get them around their necks or scruffs anyhow. They usually do some subtle thing before that even happens and people who think they're mimicking dogs are probably not. Humans can communicate something like this (and other things) in better ways to dogs and those ways have been determined by science and canine behavioral studies and experience. Our relationship with dogs is different than that of dogs with dogs.
I don't train any dog by using aversives.
If we're talking about play biting, how I would handle it is to remove the payoff the dog is getting for biting. That's me, that's the fun and games or the patting attention. Playtime is OVER immediately. I would walk away and clean out some drawers or wash dishes. I'd make sure the dog has something he can chew on.
I taught my Doberman bite inhibition as a pup. That is, I did not disallow mouthing me altogether. But if it came even close to pressure on my skin, I let him know it hurt and then I'd leave the area for a few minutes. I'd then return and try again. When he would mouth me very very gently, I'd continue patting him or playing with him.
Even now, occassionally, he'll get excited when we're doing agility, he's having so much fun and he may leap up in his frolicking and knock his open mouth against my arm. I'll squeel, "ouch!" I'll promptly end the fun and walk away. He hardly ever forgets, but once in a while.
Scaring, hurting, freaking out a dog by shaking it up doesn't let him know what you want him to do. If the punishment comes a second too late, he may associate it with a behavior which is not the one you meant. Suppose he bites and then stops for 1/2 second. And now he gets shaken. He is being punished for stopping the biting. It takes a second or two to reach over, get a grip on his neck and shake.
If you reward a dog by attention while he's mouthing gently with no pressure, he will see that that behavior is something to continue or to repeat. Nice things happen while he's being gentle.
If you get up the second those teeth make any pressure on your skin, and leave the area and all playtime and affection is over, he will begin to associate those two things...bite too hard, playtime, good things gone. He will learn, if you and all who interact with him are consistant, to choose the way you want him to choose. He needs reinforcements to figure out what you mean. Without reinforcing good behavior, he won't learn.
If you're off on your timing, either way, it can confuse the pup. However, if you're off on your timing with the getting up and walking away, no harm is done to the psyche of the dog. He simply missed an opportunity to learn this one incident. If you're off on your timing with punishment, you may be punishing a desireable behavior which will not tend to be repeated. And you are showing your dog that you are a scary and unpredictable leader and to do certain things in your presence is dangerous, not necessarily to do those things period. (in examples of other behaviors where you're not present all the time)
Punishment, when the timing is right on and when it's severe enough will stop behaviors. But there are serious side effects to aversive punishments.
So, that's why I use motivation and reward training methods, why I try to be observant in what things my dogs may consider a reinforcer or a payoff. Sometimes we have to look hard. What is it that this dog is getting out of this rotten behavior? What's so good about it to him? How can I prevent or remove that payoff? What else can I ask him to do that he can't do at the same time that he's engaging in this rotten behavior? What alternative skill or task could I ask him to do instead? If I don't want him on the furniture and he keeps getting up there, what's the payoff? It's comfy. So, what can I do while I'm in the room? I can put a comfy dog bed on the floor, maybe even more comfy than the couch. I can show him to lie down there. I can give him some extra yummy treats every so often while he's lying there to reinforce him for lying there. If he gets on the couch, I must be right there to show him again, his own bed. In fact, better yet, intercept him while he's just thinking about it, before he leaps up there. When I can't be there to watch him, I must prevent him from being reinforced by getting up on the comfy couch. I'll have to put some cardboard boxes or some other equally uncomfortable thing up there.
I do not have to scruff, yell, jerk, slap, spray, throw things at my dog to teach him to stop an unwanted behavior.