Thanks Ryan and Splinter.
Elsewhere, all the comments are about this being too much, they're able to do it freehand, their sand belt does it in a fraction the time, and so on.
The irony is, many making such comments beefed up or spruced up up their car, if not outright restored a classic, or they built a beautiful piece of woodwork, when an OSB box would function the same. In the end, it's almost comical that they believe THEIR choices, in what they do, make more sense. and it was so important they point out what is wrong with something they, really knew little or nothing anything about.
Then there is that no one I know and who owns fine steel (e.g., $200.00 or more knife) would let their knife anywhere near a grinder or sand belt to risk the temper. I have a four wheel I can vary from zero to 2.400 RPM, and it only gets to profile my lathe knives. My 1/42 sander is only for general work and touch up on the lathe knives. Maybe a mower blade.
As to time, ONCE you get the apex angle you were shooting for, my two wheel buffer (jeweler's rouge and chromium oxide) takes only a couple passes to bring, for example, my SV 110 blade back to good (push paper cuts) for another several weeks of cutting cardboard and such.
Even if I went back to the sharpener, it would be done in under five minutes, barring major damage requiring toothier stones and working up.
A little black marker on the blade and a super fine stone (all the stones are the same dimensions, so there is no shift in angle swapping them) tells me if I'm set to repeat (when it wears off fully and evenly), before jumping to the actual stone.
Anyway, there were times I thought I had sharp knives, but my expensive jigs proved I was wrong and there was better awaiting.