They are not ticking time bombs, they are dogs. They will not attack unless the owner has given up their position as pack leader. As I said before, submissive members of a pack don't even eat unless the leader says they can. All dog attacks, even the biting small dogs, can be attributed to failure of the owner to demonstrate proper pack leadership.
I disagree. They're dangerous due to their specific breeding. And I've had big, strong-willed dogs. Male Briards. Strong-willed owners can control strong-willed dogs, but the genes are still there just waiting. You can't breed dogs for centuries and not expect that very breeding to show up. And, just what were these dogs bred to do? Also see my early post. I think it was #23.