Lol,hadn't heard of those before!
TBH all the tech stuff about Jap blades went over my head DefMunky,but I found it interesting nonetheless - I agree about the metal polish,that works a treat! I've sacrificed a few leather belts myself,but never got as good a finish as I have with plain old brown paper or news paper,so I stick to what I know works for me as it's a purely functional blade & I strongly dislike cutting myself while shaving..
Tho I do have a pre- Napoleonic razor that I use for special occasions (first dates,Xmas etc) that I cosset & look after "by the book"
Must admit,your sushi knives sound lovely :-)
https://www.instagram.com/inkitatus/