I have observed the effects of careful training and disciplining of German Shepherds by my daughter and her husband. You speak of dogs as tough as nails, totally under the control of their handlers. Too many times, however we’ve read of dogs that escaped from their fenced confines or were permitted carelessly to wander, obviously then not under control of anything other than their own animal impluses, with tragic consequences. Like it or not, if given a choice, I’d much rather ancounter a cocker spaniel, border collie, or one of a number of other breeds than a single pit bull, and two or more of them in company, which seems to engender an attack pack mentality, would give me great concern. For the most part, dogs seem to sense that I am a dog admirer, inclined to talk to them and pet them if given an opportunity. But I have little confidence that a pit bull would sense that attitude in me.
I’m not familiar with Pitts at all. Never had anything to do with them. Years ago, I did raise German Shepherds and yes, they have the pack mentality, especially if attacking another animal. In general though, they are very safe to be around if trained and socialized correctly. Mostly, the problem with these dogs is the owner.