I find that vertical joints are troublesome to say the least. No matter how good the hanger/framer is there is always a "bone edge" or factory edge that is higher than the other. My normal method of finishing vert joints was to box using a 10" box then 2nd coating with a 12" box then do a minimal brush off sand between 2nd and 3rd coat (not final sand just enough to get edges down):thumbsup: roll skim using a 14" paint roller troweled behind with a 14" knife to get pins out and float out uneven factory edges. Ive never had a problem with this method though a little time consuming. The company I work for now refuses to do a 3rd coat saying they dont have time but they are constantly fixing humped walls or bone edges during point up. Ive ran a 8" 10" 12" box method before but still have probs with the factory edges.