I've struggled a bit with tool sharpening, but I've found I get really nice results when I get all autistic about it and make sure to grind the bevel completely flat for each successive grit. So I had the idea of using a permanent marker to stain the bevel so I could see when all the high spots were off, but it tends to be washed away, even with waterstones.
Is there some kind machinist's blue that's appropriate for this? I was thinking maybe giving it a try making my own with some alcohol, shellac and Prussian blue. Or maybe even acetone for extra quick drying.