Glen
I still haven't had a problem with the scales, granted the scales are on older straights and are original therefore they aren't the prettiest things around but still I haven't done any damage to them.
Would I try this with a custom set of fancy scales, No, but then I wouldn't do any of this on a custom made razor.
And Midway carries a product called liquid sandpaper, you can "paint" it on a buffing wheel and let it dry and then use it to sand the razors. Great stuff, I used some on a stitched wheel and tried it last night.
Ted