This perplexes me. Is it because you feel sorry for that last sheet clinging onto the old roll and you are hoping beyond hope that it will remain there, unused, forever? Perhaps it is an underlying fear of the “what if’s?” What if the spring in the spindle malfunctions which forces the spindle to pop off, ricochet off the mirror and somehow make a beeline for your forehead? Maybe the pressure of the “under vs. over” is too great. Lots of sleepless nights have been suffered because of this baffling situation.