What if instead of going through the tedious process of radiusing a fretboard (I do it by hand and it takes forever), you just keep the board flat and radius the frets with a block and sandpaper one they're on the fretboard? Obviously this wouldn't be a good idea with a small radius and small frets since it would take a lot off from the edges, but if your using jumbo frets and a 20", or maybe 16" radius, could something like this work? If its possible, you could level the frets and add the radius at the same time, and in less time