You certainly know more about steels than I do, Daberti; but I was not criticizing your post, but rather the tester in the YouTube video who said that the relatively poor wear resistance of the S35VN blade he tested was due to a poor heat treat. The problem with his statement is that he tested only wear resistance, not edge stability or toughness. The heat treat could have been fine; it was just optimized for toughness, not wear resistance.
From Sandvik: A higher tempering temperature will yield a somewhat softer material with higher toughness, whereas a lower tempering temperature will produce a harder and somewhat more brittle material
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A camping knife or a survival knife, for example, may be tempered at 350°C so that it will be able to withstand rough handling without breaking. On the other hand, if the knife is expected to keep a sharp edge, it can instead be tempered at 175°C for maximum hardness.
http://www.edge-1.com/Edge/stores/afri-thipa/articleimages/SandvikHardening Guide.pdf
So heat treating can be optimized for toughness or wear resistance or some other quality. Just because the wear resistance is somewhat low, doesnt mean the heat treat is poor. It may mean that the heat treat was optimized to emphasize toughness over wear resistance.
Typically, wear resistance on powder steels like S35VN is excellent, but toughness is average. (See chart from link above.) So it may make sense for a tough-use knife with a blade made out of powder steel to kick up the toughness at the sacrifice of wear resistance in order to achieve a performance better balanced for the intended use of that knife.
If a knife maker is going for any particular characteristic (toughness, wear resistance, corrosion resistance, edge stability (resistance to chipping and rolling) or sharpness, he has a lot of choices. He can change the heat treat to stress one or more characteristics and he can choose the appropriate class of steel. And he can choose the best alloy within a steel classification. So if he wants high wear resistance in a powder steel, hell choose M390 over S35VN. If he wants exceptional toughness in a powder steel, hell choose 3V over M390 or Elmax over M390 if he needs stainless.
If he wants a blade easily capable taking a keen edge, he can choose a fine grained steel like 13C27 or a carbon steel like 1095. Hes not likely to choose a coarse carbide steel like D2, which is a bear to sharpen to a keen edge. On the other hand, if he wants wear resistance, hes certainly better off with a coarse carbide steel like D2 or a powder steel like M390 than he is with a carbon steel like 1095, which excels at toughness and edge stability, but is poor at wear resistance.
You could say that ZTs heat treat of its 0560 S110V composite blade was terrible because it was run at a relatively soft 59Rc, leaving lots of the performance potential of that steel in the oven. On the other hand, ZT, on that blade, was heat treating with beauty in mind. It wasnt a bad heat treat, it was a heat treat with a specific mission: a composite blade. To my mind, that knife was intended more for collectors than users, and the heat treat was optimized for that purpose.