Well I guess, I'm in the minority, I have used my dremel and flitz to polish a number of internal parts with out any problems. But I am careful when I do this.
My sigma trigger improved 300% after some dremel work, not to mention a number of Mosins and enfields that went from horrible to good triggers. Now I have pistols that I don't touch. but I think with care and patience a dremel can be used without problems.
I am not a smith, nor did I stay at a holiday inn last night ;-)
Croc4