A fascinating link. The anecdote towards the end, ending in the phrase, " leading to the (surely apocryphal) story that Dorothy Parker remarked on meeting him, “So you’re the young man who can’t spell fuck?”" is one I heard of Tza Tza Gabor to Paul Brickhill, author of many novels about WWII in which he uses the euphemism, "muck."
This probably supports Quinion's claim that it is apocryphal.

I'm immortal until proven otherwise