"In actual practice, a dog with a small head with proper structural mechanics, has the advantage."
I would ask an AMPT breeder what "practice" this medium size but structurally sound structure gives it an "advantage" in besides effectively dispatching other dogs. Here is another quote from the page Bahamautt99 referenced:
Wide and deep muzzle is very important. Why wide and deep (not exaggerated)? A straight, box-like muzzle and well developed mandible will not have much to do with the biting power but will endure more punishment.
And this from the
Temperament Page of the same site
Our breed is in mortal danger because too many dogs with fear and human aggression are being bred. People do not realize that temperament is 80% (some say more) genetic in dogs.
Regarding aggression in the breed: 1. DOG toward DOG aggression IS a characteristic of most terriers, including the APBT.
2. DOG toward HUMAN aggression IS NOT a characteristic of the APBT at all in any form.
Once again, perhaps not a great choice for the doggy day care play pen. I am sure that there are many ABPT that are not dog aggressive, but can certainly not fault Petsmart for making the business decision that they will not try to distinguish which is which.
I have no personal knowledge and have had very little interaction with the breed. I do know that backyard bred pits and pit crosses make up a huge percentage of the dogs in the kill shelters in my area, 40 to 60%. This is heartbreaking for anyone who loves dogs, and I imagine particularly so for those who fancy the breed. For some reason more pits and pit mixes are bred than there are people who want to live with one.