If we can bring other people than ourselves into it my own father half tore off both of his index fingers trying to rip a beer can in half like he'd seen on TV. Turns out the edges of the opening on a beer can are sharp and if you manage to fit both of your index fingers in there and you are convinced enough that if you just pull with all your strength you can rip the can in half, you are correct about everything except what you are going to rip in half.