Observe that the paper tears after the thumb down the grain. Naturally ! Why would one expect it to do otherwise?
Tears begin preferentially at sharp corners. The perforations in toilet paper have such corners, perhaps because no attention is given to this parameter. (It's too small to bother with.)
Let's bother with it , shall we?
Here the perforations are shaped in "S" forms slanted to one side such that the end of the perforation starts the tear along the grain as before. However, the bottom of the next s-shape catches the tear and transports it to the next s-shape tear point.
See? It acknowledges the grain and exploits this simple fact rather than ignoring it.
This makes for a "right-handed" toilet paper, i.e. if you begin tearing at the other end it won't work.
Therefore, the Ebtex conjecture:
"If two lines of perforations are made (one right handed and one left handed), the one that tears will be the correct one (no mattter which hand you tear with) and there will be peace in the world."
Applause ... applause ... applause...
THANK YOU . . .
P.S. This has probably been thought of before but I also thought that they ought to use velcro for kids shoes when it came out.
TEN YEARS LATER it was on the shoes.
But it's really not important enough to do anything . . . . . . . . .