Under, but fold the beginning of the paper over itself, so it appears to be over until your unsuspecting victim tries to grab some paper. Then they realize the true nature of your depravity.
A few years ago I chose to stop thinking about it. I just refill the roll and don’t worry about it. When I realized it didn’t matter, it was a weight lifted off my shoulders. Same with trying to stop the gas pump on the nearest dollar or setting the tv volume to an even number.
I don’t know why I felt such a relief when I let go, but I did and now I’m free!
Over is best for high rate on a household single roll holder, but if you ever load a bathroom stall toilet roll magazine its gotta be under or the next round wont cycle into chamber
Under because that way you can model it by making a cylinder and adding a plane to it, because the plane is attached to the back you don't have to do the extra work of making sure the textures line up.