Ian,
I get that. The repair that got me going on this was a Gibson j-150 which had been hit by a shoe. There was a lateral crack in the finish right along a grain line and to be honest I reglued the braces, put a little color on the exposed wood and then started right in with the fill-n-finish without sanding the surrounding area at all.
I used the tape over the razor blade method and then started stepping up sanding sticks from about 800 up to 2000. I’ve added 4f and rottenstone powders to my arsenal (which have been awesome) so I took it to a almost full gloss with that and then hit it with a light polish. The lines showed through and I always hate sanding on any finish any more than I have to.
I may try the acetone vapor (obviously on something else other than a good Gibson jumbo). And report back, I just wanted to see if anyone had ever gone down this path. I always end up trying to reinvent the wheel.