Given that you can buy lock on grips these days for less than a tenner it's going to be a moot point really...
...but that doesn't help you with the job in hand.
My preferred method of removal and reinstallation is as follows:
1. Pull and twist whilst repeating "Let go of the bar you ####!"
2. Berate world for the futility of task in hand. Wipe sweat from forehead and kick nearest four legged mammal.
3. Utter "You complete #######!" and slowly peel back the end of the grip nearest the brakes while applying constant force to the grips.
4. Apologise to the now wary four legged mammal and offer concilliatory treat.
5. The grips will loosen and release with a sudden "Pop!" causing your hand to fly sideways and smack your knuckles on something.
6. Apologise to cat/child/wife etc or rinse grit from wound on knuckles, or apply cold pressure to your new black eye depending on who or what you've just struck.
7. Fit new bars to bike and attempt to push old grips back on 1/3 of way. Slap forehead.
8. Realise you have a can of spraypaint nearby, so remove grips again and spray inside before refitting.
9. Wipe excess spray from bike/furniture/cat/wife etc.
10. Viola! Leave for twelve hours for paint to set and you should now have grippy grips again.
This method served me well until I bought lock ons, now all I have to contend with is the rounded bolt conundrum which means I have to break out saws and or drills each time....