I broke mine this morning and messed up the tip of my left thumb some kind of bad. Have you any idea how hard it is to slice that little bit of apple seed area off with only 9 digits? Yeah, I still had the prehensile movement going for me, but as my left thumb was happiest up and away from any more sharp things? It was more of a battle than it need be.
Thankfully I am right handed. Otherwise I would not be here typing this, what with the spacebar and thumb connection. I knew it was too good to be true that I didn't throw out my back with all the recent furniture moving...urgh.