Welcome to the forum first state.
I posted this on another thread that asked about bite inhibition. The beginning was specifically for the other thread but here goes.
Many puppies do a lot of biting this is one of the ways they learn and experience their world. It is natural for them even if we owners don't consider it appropriate behavior. They need a lot of training to learn what is acceptable and during the process they usually need to be managed (when they get over excited they need to be put in a crate, x-pen, and given something quiet to do. Over time you will learn if you watch them and can stop play or slow down play doing more calming behaviors before they get over that threshold.
(this part applys to the other thread)I personally wouldn't do either.
The reason I wouldn't squeeze or put any preasure on their nose/mouth is because I don't want my dog to ever think I will cause them discomfort.
It is a traditional method of training and works well for many owners and their dogs, it just isn't for me.
In the 4 quadrants of operant training it is what would be considered a positive punishment. Positive punishment = adding something to lessen a behavior (preasure to the nose)
Looking at the spray bottle of water it is also a positive punishment. Again adding something to lessen the behavior. (water to the dog)
These traditional training methods may teach the dog faster but may also break down your bond of trust. Mom's hands cause discomfort. Mom is unpredictable and may squirt something in my face.
It also doesn't teach the pup to learn to use their mouth gently.
I prefer holding a low value treat in between my thumb and index finger and giving the dog the treat. If the dog bites hard I say ouch loudly and do not give the dog the treat. I wait for this to go through the dogs mind and try again. After a few or a lot of times not getting the treat the dog takes it more gently I say yes and give the treat. You are looking at increments of the bite changing. It does take some time.
In operant conditioning this is a form of negative punishment. Negative punishment is subtracting something to lessen a behavior. When the dog bites hard you are not giving the treat.
This training set up does not cause the dog any physical discomfort.
The reason I believe we have seen more traditional training and use of positive punishment in the past is that it is easier to do an action vs an inaction for us humans.
Squeezing the nose = action.
Spraying the water = action
Not giving the treat = inaction
One more thought to this. When applying the preasure (you do not allow the dog to make the choice)
When presenting the food the dog actually has to process this through his/her brain and make their choice.
Dr. Ian Dunbar's book "Before and After Getting Your Puppy" has a chapter on bite inhibition. In the hardback book it starts on page 135.
There are links somewhere on DogStarDaily to this book separated into Before you get your puppy and the other one is After you get your puppy I am not sure but it might be in there also.
video by kikopup
video It's Yer Choice by Susan Garrett