Definitely!
That is an interesting take on abstract vocalization (if that isn't already a term i'm coining it). I've personally never had to do it but i've reversed vocals before just to see what would happen and you can get some pretty cool/spooky results. I believe this is how the voices for "Shadow of the colossus" were done.
Those No's were splendid and are the most most important part of the game!
Thanks for sharing!