I don't think it's rare for appraising to be useful to at least some extent. Is picking up a bunch of weapons and then dropping the ones rated at "mediocre", really such a rare event? What about a situation where you have an armor swap that is normally an improvement, but would be annoying if the new armor is cursed? Either a "fair" or "mediocre" assessment is helpful. This is in fact the first example I found looking through VODs; current armor uncursed leather, new armor "good" studded leather, so I know it's a safe swap to make.