On both the Crimes and Mythdemeanors and James Bond Special episodes, it is mentioned that Jamie's ultra powerful magnets would cause one to lose a hand (that is the description that is used both times). That sounds like a wonderful myth to test. What kind of damage can those magnets actually do to the human hand (or ballistics gel equivalent)?

Put your hand in a bench vise and have someone tighten it as much as they can. How does your hand hold up?