: I have yet to sand a finish (speaking of furniture) that it didn't dull the
: finish. I sometimes will go over a piece with 1000 to 2000 grit, (yes
: thousands) to remove the nibs. I even do that very lightly! But if I sand
: a single spot more than just a little, it's going to show. And I have had
: no luck touching it up. I have just worked on laying down a better surface
: with no runs.

: I have not tried this, but I read about polishing varnish with automotive
: polish and a polisher. The results were spectacular. I have the article
: somewhere.

Last night I touched up a few deeper scratches and dings in a stripper I finished about 2 months ago. Lets face it, if you use the boat, it is not going to look like fine furniture after a few outings. I have a few sags from the final coat that I just left, I think it is easy to get obsessed with a fine finish on an object you are going to run into rocks, drag across pebbles and sand, etc. I plan (hope) to do a better job when I sand the boat out and re-varnish in the winter, when the bugs go away.
In the string instrument world, wear and tear (antiquing!) and texture in the varnish are considered to add character, and new instruments are often made to look beat up. Maybe some day, the Strad of kayaks (an original Guillemot!) will be valued even more for its wear and tear and signs of being hand made.

Ken