20º very difficult to grind. Why do you need these very unusual angles, skews etc?Depends who you are apprenticed to!Some might, many wouldn't, because if you are not bothered it's faster and easier to just do a rounded bevel. You don't have time to f about with jigs, glass plates etc if you are on a building site In fact you'd probably get laughed off.I thought you said there was no right way? What is "correct"?He ain't god but he is fairly practical - and he doesn't promote all the expensive sharpening gear and accessories that many of the others do. Even he gets a bit side tracked by modern sharpening nonsense and burbles on a bout "initialising" chisels.
I wonder if he christens them too?