old Ed Landers says that if do a proper bone/charcole case hardening job you won't have any problems.that you get in to problems when you spot anneal frames while doing torch coloring jobs.you essentially take the temper out and soften the metal and this can cause premature wear and part failure.if you anneal the frame by heating to different temps(this is what gives the colors you see on a torch color job)this will cause metal fatigue and possible stretching of the frame.