Originally Posted by Smithy
Bob Kramer is a great salesman, that's for sure.
One principle to remember about knives, is that two things affect sharpness. This goes for your kitchen gear, your field gear, or even your sword.
1. Edge geometry, the shape of those two planes intersecting, determine "how sharp."
2. Metallurgy and the heat treatment of your steel, determine "for how long."
I can put a razor's edge on a stainless crap butter knife. It just won't stay there forever. You can buy expensive stones, jigs, and tools, to get a consistent process made easier. You can find a handful of rocks in the woods that will do it too, if your technique and consistency is good enough. The secret, if there is one, is what Bob mentions in his video there, consistent angle and pressure... along with what I contend is an oft-unrecognized part, which is the condition of the edge. Those very fine stones, above 2000 grit, polish more than remove mass. A polished edge has no "tooth", and doesn't saw, it slices. It can be like a little lightsaber in your hand, and may not appear sharp using the usual calloused thumb test.
The sharpest blade, if not made of an adequate steel that was also properly heat treated to ensure edge retention will not stay sharp as long as one made for that purpose. Two knives of the exact same metal can be made for better edge retention, or easier field sharpening where you don't have all the fancy tools available. Some of the modern super-steels try to achieve both, with mixed results. It's always a trade-off, and there's no one knife that will do it all, all the time, as well as a specialized tool.