Ultimately, there may never be a final answer to the over-versus-under debate. The choice is largely a matter of personal preference, and different households will continue to do things differently. What matters most is respecting the habits of the people we live with.
In the end, the toilet paper roll may be less important than the way people respond when their preferences clash. Sometimes, keeping the peace and showing flexibility can matter more than proving who was right. After all, a peaceful home is worth far more than winning a small argument.