Nope... never failed me. In fact, in reflection, it has surprised me how well it did work without having to think about it. I really don't go looking for a fight, so when it happens, I am not the aggressor and I have always walked away from it. The other guy wasn't always beat to a pulp, but he got the idea in pretty short order that he might want to pursue his thuggish intentions with a less capable target. I love to embarass a bully in front of his friends.
True about knowing when to keep your mouth shut too. Good point. Too many vocal friends and it is just best to remove yourself from the situation all together.
James