David Weaver
Yes - and fortunately for us, all of the really good edge holding steels temper at regular oven tempering temperatures.

Actually, I can't think of anything I've tempered below about 330F or above 425F.

52100 poses two problems for me, though - I don't have enough heat, and I don't have enough hammer. I do have the ability to soak it fairly accurately, though, and the kind of refinement that the knife makers really love may not be needed for chisels (or in short, the problems that calton has if the steel isn't done just right probably wouldn't be noticed in chisels).