Surely questions of readability should be decided with an eye towards experienced users of the language and not those who "don't know the first thing about F#".
I agree with the GP that x::xs is more appropriate.
I do not think that phrase means what you think it means. If the code is readable to somebody of average skill who has learned the language, it is not "write-only." The fact that you can't read code in a language you don't know shouldn't surprise you any more than the fact that I can't read a book in Vietnamese. My inability to read Vietnamese does not make it "write-only" — it's just a sign that I haven't learned the language.
As for "fringe," that may or may not be true. It's pretty subjective. But really, who cares? Back when Ruby was the weird new thing gaining visibility, I heard the same complaints about its idioms. Last I checked, it's still doing fine. I'm OK using "fringe" languages like Ruby.
I agree with the GP that x::xs is more appropriate.