Of all the stuff that can cramp your hand, removing old crusty gaskets is the worst, WORST of them.
I tried using my Dremel on my last gasket. I have a slew of bits I never get to use, so I started experimenting with them to see which ones would not be too abrasive on the part, I didn't want to cause any low spots. Turns out I had a set of hard green ones that worked wonders. The gasket came off quick and left a nice smooth surface. The Dremel bit wore down quick, so I went through a few of them.
To me, it was worth it. The bit's cost a few bucks each, and the time/effort/frustration saved has me wondering why I never did it before.