Well, I finally got a chance to ask my friend the former flight attendant who bragged to me about being in the mile high club. She said:
Happens all the time, but usually not with passengers
L1011’s have twin elevators you can lock in the “basement” with the center doors open for double space.
The crew usually have a bigger, better bathroom set aside for themselves.
Your coworkers cover for you
“The English Patient? Hell yeah.”