Bill Tindall, E.Tn.
Is the thickness important or could I do the same with a Stanley blade or any surplus blade........ that is, beyond the grind what other property is critical?

Just avoiding burned thumbs is sufficiently attractive.

I can retrieve pieces of planer and jointer knives from the scrap barrel at the saw shop. I am imagining such a piece ground at a slight camber being perfect prelude to sanding. Just like in planing I'm after material removal with no concern of surface luster.