So I did something weird with one of mine. What I did was I removed the head, stuck the magnet to the bottom of a little stainless steel pan, filled about an inch or a little under an inch of water in the pan to keep the pan from getting too hot, and then put the pan on the stovetop and let the water slowly heat up to a boil. I let it stay in the boiling water for a bit, and when I took the light body out, the heat had significantly reduced the magnet's strength. It also causes the glue to loosen, as a while later, the magnet fell out on its own.
I definitely don't like magnets in pocket lights.