The two comments were almost off hand comments while in a hurry and I may not have quite gotten the technique understood, but I believe the air force at the nozzle and applied under the grip's edge can be sufficient to assist with shifting them or removing unglued grips. Easier than trying to torque them off and damaging them. A possible option if in that situation.
Rubber cement? You won't be getting those grips off. I use windex...has always worked ok for me.
FWLIW, in my case, I had to cut the original grips off and didn't want the news permanently bonded....at least not yet. The Purell approach made for very easy installation for the cruiser and so far the grips are definitely on there and not moving.