Pof doesn't 'fuck the rock up'. It leaves a shiny layer of resin on the rock which can be removed with alcohol and a toothbrush. This doesn't harm the rock in any way, but takes all the resin off.
I thinks that Daves comment that pof is cheating is a little bit naive though. Surely this makes chalk cheating, aswell as sticky rubber?
the floor has been dropped by 2-3 feet
....duel carriage way....