Brian Jones said:
Cliff, what evidence do you have of how they heat-treat?
The hardness, use the relevant materials data, specifically look at the torsional responce to tempering in that range, I have listed this several times before as well explained why underhardening such steels is in general problematic for several reasons and when you are in that range of hardness, bainite is generally superior to martensite as the toughness is vastly higher, materials references for all of this has been provided in detail on rec.knives, Allen's book is a good place to start.
I have of course also actually used a TOPs knife, it isn't all just based on the
facts of the materials data, and it was vastly outperformed by other knives, including ones which are significantly less expensive. I have also used 1095 knives were are heat treated to maximize the responce of the torsional data as have others who have discussed the performance in detail on rec.knives as well as other steels far more suitable for high impact work.
Alvin Johnston is discussing steels for that class of knife now on rec.knives and the discussion is centered strongly on heat treating based on actual
factual materials data as well as testing he has done, flexing mainly to date, you may want to check out the commentary and read the revelent cited materials text to understand the critisms about using that steel for those types of knives at that hardness.
As for Bos, his heat treatment of ATS-34 was critized by other makers like Mayer who had actual materials data to support his arguement, discussed in detail on rec.knives. Jim March was the focus point of that discussion for awhile as he had customs made in the steel and got involved with conflicts among the heat treaters on how to proceed. The vast majority of heat treating now of that type of stainless has switched away from what Bos was doing to the style Mayer proposed which specifically is low temperature tempering to avoid the problems with corrosion resistance and loss of impact toughness in the secondary hardening.
As for all the "hand work" TOP's does consider :
http://www.bladeforums.com/forums/showpost.php?p=3335969&postcount=5
and the fact that Swamp Rat will adjust edge angles on user request, their blades are cheaper than TOP's, also have "hand work" done on them, have a more comprehensive warrenty, use a more complex steel and run a differential hardening.
-Cliff