Interesting, I was at Schon a few months ago when in Wisconsin and left my playing cue there to get refinished (they did an awesome job BTW, looks like brand new). My older R6 Schon was always about 1/2 oz. heavier, so I asked Evan if he could make it the same weight as my regular playing cue to make the transition during the waiting time (6 - 8 weeks) easier. He said it wasn't an exact science, since the bolts weren't incremental by the ounce, and it depended what I had in there to begin with. He put the cue on a machine, clamped it in, removed the bumper and unscrewed the bolt with some device. But from what I could see, could have used a screwdriver as well, his device just locked the blade in tighter (didn't look like a standard flat head or phillips blade) and removed it using slow but steady revolutions, probably just a high torque, low speed drill. He didn't seem to check for any glue etc., maybe he just knew that the older ones weren't glued or something...
He popped the bumper back on and left me the old bolt in case I wanted to switch back. Cue came out perfect, very close to the weight of my playing cue.
Scott