This is important enough for me to interrupt the script I have to finish today and come back here to post it. As all of you are aware I'm sure, it matters a lot which way the toilet paper comes off the roll. It should hang off the front (as in the photo at left below) not the rear (as in the photo at right).
As I wrote back here, I once did a show with Jerry Lewis and we were warned that he would walk out on the taping if the john in his dressing room had an incorrectly-mounted roll of toilet paper. I do not think the person who told me this was kidding.
In this world, there is no fact or truth so universally accepted that someone won't insist on the opposite. Well, we have now have proof — or at least as much as we're ever going to get — that the front overhang is the correct configuration. Writer Owen Williams dug up the 1891 patent for perforated toilet paper and the device that holds it. It clearly shows how it was supposed to work.
I can't think of any reason to have it hang down the back unless it's that you want to get Jerry Lewis out of the building. Then again, that might be a great reason.