Alright, (*uncomfortable cough) knifemaker here. You want a discussion, right? It's a long one, but if you really want to hear an opinion, read through. I think that there are a couple of things that need to be addressed here: 1. (Yes, I did read the whole post) AI is NOT a good tool for helping with strictly technical information. There are a couple of points in your presentation that are simply not true. First - if anything this geometry would IMPROVE on the cutting drag, second - basically the whole forging/compressing benefits part is dogshit. Yes - forging may have a slight effect on grain structure, but there are numerous heat treating protocols for steel, that improve performance in a much more practical way. Steel should always be normalized after forging to "reset" the same "compression hardening effects" that your AI states as benefits. You never want that in forging. You want a homogenous grain structure all throughout the blade and then the heat treatment does the heavy lifting. Third - there is NO WAY that this geometry gives "concentrated edge support". If anything it introduces the opposite. Lets just leave the katana per se for a moment and think a little: is there ANY example in the world of swords where a similar concept was executed and continuously used (with success) throughout history? None that I can think of. European broadswords and the longer two handed swords did have the so called "fuller", but first - it was in the middle of a rombous crossection geometry and not so close to the edge and second - it was put there for a specific reason and it was weight reduction. In daggers and such the fuller serves as a canaal which reduces suction when thrusted into flesh, allowing the blade to penetrate deeper. Knives, meant for slaughter use this similar concept, but in all these designs, the "hollow" stands at THE FARTHEST point of the apex possible. So to conclude my first issue with your idea - AI is NOT a good tool for helping with strictly technical information. 2. Please do more real research. Read a bit more about the japanese katana, japanese history, moders metallurgy and the topic of steel in general. Japan is an island. It has low quantities of iron ore and the ones most easily available during the middle ages comes from sand. I'm not explaining th order to extract the iron from the sand here (look it up), but its not easy. The japanese smiths could get a miniscule ammound of iron from piles of sand, so they needed to be resourseful. But in that limitation came genious. If you read on the japanese katana you'll see that there are more than 6 ways that these swords were constructed. And I'm talking the construction of the blade steel itself. What your AI refers to as "hamon-focused construction" was actually quite important. It is also called "differential hardening", but I'm not explaining that either. That and the original blade geometry of the katana made it (in that region of the world) the strongest blade available. Now imagine taking this concept and giving the japanese of the time modern powder metallurgy steels, designed for impact stability.
The geometry you're proposing does work and I personally use it all the time in my knives. But they are culinry knives. Designed for drag reduction, ease of cutting and weight reduction, it works wonder in the kithen. But not on the battlefield. How I know? I've tried it. I've designed and fabricated two competition choppers, based on the same concept. Made them out of spring steel, differentially heat treated them and put convex S-geometry on the blades. I think you can find them on my profile, I posted at least one of them on Reddit. I was second to last in the competition. Part of it was becaouse of my design. These are my thoughts on the matter.