Okay, I'll say it: meeeYOW.

From the murky depths of my subconscious comes the notion that the etymology of 'foul' as used here is different from the usual one. Something to do with foulard the textile. Don't have a good enough dictionary to hand. Any ideas?

I bet there is not one person at the Times has ever touched an em or en and inserted into their column. Other wise it would be foul play. Be interested to see if any one escaped from the galley and ate humble printers pie(with cream of course, medium black).

Way back, in 1966, Doubleday published my novel "Easy Terms" set in Paris in the 1960s. My brilliant editor was Naomi Burton who had accepted agent John Schaffner's recommedation.
I wrote another novel, set in New York, which I called "Foul Matter". Recently I resurrected the typescript which, in spite of John's sterling efforts, remained unpublished. I thought I'd check to see if anyone else had used it -and found that Martha Grimes had done so several years ago! My title punned on the antique spelling of the letter S - Soul Matter in 17th century English. I thought it might appeal to Naomi (she was, of course, Thomas Merton's friend, editor and publisher)
Naomi left Doubleday just before Easy Terms was published. Well reviewed but totally unpromoted,it sank without trace!
When it was remaindered, Doubleday posted 50 copies to me here in England. As they passed through the NYC Post Office, the building burned down! So Easy Terms remains one of the rarest books in the world!
Will have to reread Foul Matter. I do use the expression sometimes, to people's bewilderment.

Thanks for sharing that story, painful as it must be. And it is a great term; I wish I had more occasion to use it.