Not that it would be a significant factor in a survival situation, but there's also the legal aspect to consider. In Montana, at least, shooting a griz is about on the same level as shooting a man. If by some miracle he hesitated and you killed him before he got hold of you, you'd have to explain to DFW why the endangered species has a hole in its noggin and you don't have a scratch. Of course, as has been pointed out, playing "rag doll" with Smokey makes it tough to draw a weapon. So it's a lose-lose situation: deal with the bear or deal with the bear's lawyers.