This is purely anecdotal, and obvious a negligent sample size, but it's fascinated me for years.

In my life I've only seen 2 violent dog encounters, and both were initiated by a pit bull.

In HS during a baseball game a pit bull was off leash behind the field, and kept harassing a man trying to walk his own dogs. The man got between the pit bull and his dogs and the pit bull latched onto his arm and wouldn't let go. His entire forearm was red, covered with blood, and my coach ran over and was hitting the dog on the back with a baseball bat to get it to let go.

In the other case, my mom's neighbor had a pit bull and golden retriever that were raised together as puppies. Somehow they got into a scruff in the yard as adults and the pit bull got hold of the golden's neck and wouldn't release until it died. Extremely sad and disturbing.

After that, and all the statistical evidence I've seen, that's enough. I know what I believe. I've encountered thousands upon thousands of dogs in my life, probably like most of you, and as I said these examples are the only violent encounters I've witnessed.