That must have been yet another instance of "The Muse" providing humor unbeknownst to me.
Usually, if it's actually FUNNY, it just sliped out of my fingertips and surprised me as much as anyone. If I have to
think of a joke, it usually isn't very funny.
In this case, I didn't even NOTICE it: I thought I was typing "Tee Shirts".
I would have been too embarassed to type "Tee Shorts", let alone shorts with THREE phosphate groups!!