I personally don't wipe.
Most Helpful Guy
The right way to hang Toilet Paper is not at all. With all the innovations we enjoy these days it's amazing that Toilet Paper is still considered an adequate means for proper bathroom hygiene. With modern plumbing Toilet Paper is obsolete, we should be washing with water not smearing with wads of paper and the best way to do that is with a Hand Held Bidet Sprayer. Better than a Bidet and 10X cleaner than Toilet Paper it's healthier also. See www.bathroomsprayer.com
Most Helpful Girl
I heard someone say once that their friend worked as a maid at hotels and they always did under so I started doing that. However, I noticed noone else does it that way and I personally think over is better than under since I feel like it is less likely to touch the wall.
So now I start to do under but I usually correct myself and then do over.
But I still have no idea which why to do it and I do feel like this is one of the great unanswerable questions of our lifetime. :)