Here is my 2 cents for what it's worth.
I was just chatting about breeding etc at my vets the other day when I was getting the ultra sound done on my (YAY yes she is pregnant) bitch. I won't bore you with how much I've spent since I acquired this bitch on training her, and showing her to earn titles, but it is a significant amount. 5K+ for certain.
People like me show and breed dogs as a hobby. What I said to the staff at the vet clinic (as they laughed and petted my bitch as she carried her candy basket around to visit with them) is that in order to breed properly, you must do one very important thing.
YOU MUST LOVE YOUR BREED.
Your breed, and what is best for it, must come before ANY of your personal goals as a breeder or exhibitor or trainer of dogs.
Therefore, when one has a deep and abiding love and respect for their breed, one would never make any breeding that would have a detrimental effect. So people who love their breed DO ALL HEALTH TESTING before they would EVER consider a breeding.
APBTs and AmStaffs not only have hip issues, they are RIDDLED with inherited heart issues, and should, IMO also have eye and thyroid testing before being used for breeding.
Breeding dogs and creating new life is serious business. Surely you would want to do what is best for your breed, and the innocent puppies that are being created through your breedings?
If you are interested in finding out more about health testing, you can visit these sites to learn more information.
Orthopedic Foundation for Animals
Canine Eye Registry Foundation