As long as the blade stays stationary and does not move/slice forward & backwards, then it will not cut through the material nor the skin.
Next time you cook a roast, take a (non-serrated) knife and place it on the roast. Apply as much pressure as you can straight down (e.g. no back & forth); you are unlikely to cut or cause any damage to the roast.
Thanks a bunch! How am I ever going to watch ice dancing now without thinking of a knife pressing down on a pig roast