There is a book case in my parents' house that me and my father built about 6 years ago. It was built to fit around a dresser and mirror. It's a log house so everything is "rustic". We had to build it in three pieces to fit it in the room it's in. It's not the best book case in the world. We just needed something and didn't have a lot of nice tools setup at the time. I'd do plenty of things different if I did it again.
The problem is the finish. We did one, maybe two coats, of polyurethane. I can't tell you the brand or whether it was water or oil based. We just brushed it on, being careful not to have drips run down the finish. We installed it and it has housed my books for almost a decade.
The issue with the finish is that it feels like the wood grain is slightly rough. I don't notice it so much where the books sit as with the top and sides. When I used to dust it, it really caught the duster. Now, my books are still there and it bothers them. I can remove my books temporarily, but I don't care enough to unscrew the L-brackets holding it to the wall and I really don't want to carry it downstairs.
Could I use a high grit or wet sand paper to knock the finish down to where it's smooth enough not to catch the duster? Also, would there be a lot of sanding marks. Minor marks that might stand out on a highly polished table wouldn't matter here. It's just made out of some home depot boards and has a generic polyurethane on it. The rest of the house is wood/rustic. I don't want to put a lot of highly visible blemishes on it, though.
They actually have a similar problem in one of the bathrooms. The interior walls are tongue-and-groove and they'll catch towels and washcloths if you try to wipe them down. You have to wipe them down, because they also catch dust. I used to just vacuum the walls.