I have seen some honest Nanoha/Yuuno shipping, though I think there's a degree of denial to it. I've also seen some Fate/Nanoha/Yuuno OT3 stuff that I'm fond of, though the poly ship to back has always been Hayate X Wolkenritter.
At any rate, I love NanoFate, but I am always a little tickled by this comic's (and a few others') portrayal of Fate as desperately in love, and Nanoha as ace and clueless. I don't think it's really supportable — Nanoha clings to Fate at least as often in canon as vice versa — but it's funny.