^ I have no way of measuring it, but my guess is the modified heat treat does not increase impact strength as defined by energy absorbed in a break. In fact I have no way of visualizing the structures involves, but my best guess is the modified heat treat does what it does by reducing "areas of stuff" (precipitated carbides, retained austenite, structures formed from the conversion of RA and other gunk) that act like the perforations in a postage stamp, weakening a fine edge. Also, I expect the harder stronger tetragonal martensite supports the primary carbides better than weaker carbon lean martensite. I don't know *shrug* there is no SEM or x ray diffractometer in my shop. But I don't think there's in increase in impact strength or lateral strength as industry would define it. I think it boils down to the structures formed and their behavior in a thin section. There are idiosyncrasies with this alloy. The SHH would probably have somewhat higher abrasion resistance but it would not be much. Some alloys, D2 for example, develop a lot of their abrasion resistance from the formation of secondary carbides and even on that material the difference is small. 3V has a significant amount of vanadium primary carbides that are not greatly effected by the temper used and these carbides provide the majority of the abrasion resistance. Making a little more carbide is not going to make a huge difference. But the ability of the matrix to support those carbide makes a really big difference in real world edge retention. These tweaks were never about making the steel tougher, it has always been about addressing the chippy mushy edge that so many people have come to accept as normal in today's steels. What good is abrasion resistance in a chippy mushy edge? It's all about edge durability, edge stability. Therein lies the problem with edge retention testing that apply a careful applied light force against abrasive media, it will tell you all sorts of weird things like S30V having great edge retention etc. Most folks don't sit and lightly saw at abrasive card stock. Real edge retention testing requires a different approach.