I don't have another 700c wheel to try on it (my other bikes are 26" and 650c), so that's not really an option. When I looked at the sides, they seemed similar to the rest of the rim--and yes, they were slightly out of true, but it's about as good as I could get it. Probably no more than a millimeter off. I don't see any major kinking, or divots along the sidewall, and aside from the excess grabbing and the fact that the joint is there, there's nothing remarkable about that area of the rim. It looks just like the rest of the rim, and feels the same to the touch, only the brakes seem to grab it like it's sandpaper.
I don't think living with it will help, because it has only gotten worse with use. I'll try a file, since that is more aggressive than sandpaper, and I can't think of much else to do at this point. To be somewhat scientific, I'll also test another area with the same method and see if it gets worse or better.