Dang that was a lot of reading. Bit in the a@# by my pledge to read entire post before replying.
While respecting Catherines right to choose which dogs she wants her children around, I must caution that saying Breed A is always dangerous and Breed B is not does not sound to me like a wise or well reasoned choice. Any dog of any breed can be dangerous.
Nature vs nurture... both work together to determine the dogs behaviour, but I believe that nurture is the greater determining factor. That being said, there are some dogs that are overly aggressive and cannot be trained or nurtured out of that behaviour. A responsible dog breeder or owner will put down a dog who is overly aggressive or cannot be controlled or contain them and prevent them from breeding. But that is true for all breeds, not just pits, rotts, or whatever breed someone may have decided are dangerous.
If a dog is bad, whether thru nature or nurture, then that dog will be more dangerous if they are a large, strong breed than if they are a a dog that you can simply punt away. But in my experience, I have found small dogs more likely to bite than large ones. Most are not intent on killing or eating you, they are just playing dominance games.
I have owned an Austrian Sheperd (kinda like a german sheperd) and two Australian Sheperds, and love all dogs and animals. I have friends with pitts, and with rotts and with dobies, aussies, rhodesian ridgebacks, border collies, collies, heelers, daushunds, chiuauas, dog breeds ad nausem. I have found that while a particular breed will share some similiar traits (that is the purpose of breeding them after all, to refine those traits) , each dog is an individual and will behave in a unique and sometimes unpredictible way.
In the end, I have to go with those who say 'blame the owner, not the dog'.
JMAO