The use of heat concerns me a little though. The prop is perfectly fine, I just wanted to remove it, to make sure it does in fact come off in the event that I HAVE to pull it off (knock on wood). I just worry that with heat, even minor amounts of it, could deform the prop and throw it out of balance.

I've cranked the prop puller way down, and have tapped/beat the puller with a ball peen and a rubber mallet. I left pressure on the puller, and will go back out in a few hours to try. I suppose maybe penetrating oil might help...