I often wish that the production companies and custom makers would actually describe the design process that leads them to develop one particular knife over another. But that seldom happens. A knife is a tool with a purpose. That purpose can be specific (machete, box cutter) or broad (EDC). The basic knife design flows from that purpose. Blade and edge geometry also flow from that purpose, as do the characteristics of the steel used.
As this thread suggests, the thinnest geometry and most acute edge profile give us the biggest bang for the performance buck, but there are limitations, such as cost of materials, cost of high-performance production methods and the properties of the steel.The steel is as critical as the design and the geometry of the blade because it is the steel that determines how far we can push geometry and design, which is another way to say that steel determines how much performance we can build into a particular knife design. How well any steel can be pushed by geometry depends on the steel alloy, the grain structure and the purity of the steel (to avoid inclusions that can lead to surprising breakages at the worst possible time). And then there is the heat treat, which is something of a black box. In one of his books, Ed Fowler talks about a lengthy and complex heat treat that he put on a blade of 52100 steel. The result was a blade with extremely fine grain structure that could be flexed at wild angles multiple times without taking a permanent bend.
But how many times to we see a knife maker or production company talk in any meaningful detail about the design elements, geometry and steel characteristics that support the purpose of the knife? I don't remember ever seeing that kind of detail. A couple knife makers here do talk about heat treat, but they are the exception. A couple talk about geometry, but they are the exception. Most of use have way more knives than we can use, and we respond like any consumer base to marketing hype. If you can't hang 1,000 pounds off the handle of a locked EDC, we don't want it. No one talks about the design limitations that come with an EDC with that kind of strength. The most common criticism of the Spyderco Military is that it has too delicate of a point. I look at the fine point as a positive feature that allows me to do more detailed work with the blade than I can with most other EDCs. What's the point of the Microtech DOC's nightmare grind? Who knows. Why does the ZT 560 have such a thick blade? Who knows. Why is extreme jimping so popular and no one talks about how the natural curves of the handle allow it to be held securely without jimping? Don't know. I would still argue that most people here don't value geometry or edge profile.
I suspect that most people here, if they profile their edges at all, go with 40 degrees inclusive or higher. Steels designed with a mixture of alloys and treated for purity and fine grain structure are dismissed by many as marketing hype. I recently acquired a beautiful custom fixed blade in Elmax that I like a lot, but the geometry is so heavy that I don't know if I can use it. The tang is 0.19 inches on a blade 1 inch wide. It came with a 50-degree inclusive edge that was dull. I reprofiled it to 30 degrees. The steel was wonderful to work with and took a fine edge, but the edge shoulders are 0.053 inches wide. It's a beautiful, well-made knife with excellent steel that appears to have an excellent heat treat, but the geometry is too heavy to be a practical, high-performance user.
To me, the problem is that most knives bought and sold are simply for collecting; and that means knife makers are looking for catchy designs that will sell, rather than skillful designs that are designed for high-performance use.
