I used to attend a dog park regularly with my full blooded Pitbull. He never once started a fight. Not in his entire life (and sweet towards everybody he met). Usually, however, it was a Boxer that went for him, but one time it was another Pitbull. Grabbed him by the face just like in that video. His dumbfounded female owner just stood there panicking, and doing nothing, while I was yelling at her to get her dog off mine. Finally, someone came by and squirted water from his water bottle into the gripping Pitbull's mouth, causing it to drown and then let go.
Pitbulls, though, are not for everyone to own, in my opinion. They require a competent owner and handler, because of their capabilities.
