i don't know if someone mentioned this (this thread is long ^^) soo:
what if we're asking nvidia the wrong question? i think they can't communicate some kind of pascal support in macOS, they are not doing it for maxwell or 7xx series card either, not even beta support. apple would go nuts if nvidia would do so (i really hope egpu's will be a thing in apples universe, this could change a lot). i think nvidia will always respond that pascal isn't supported in macOS, they won't even mention anykind of webdriver support even if it was there.
so, at the moment nvidia webdrivers are version 367.15, no pascal support. pascal support starts with 368.25.
pascal support is already in cuda (useless without webdriver), so i don't think nvidia would remove it from newer webdriver versions.. IF they're going to continue them. maybe they are just adding support for newer OS without changing the driver.. who knows.. not getting an answer is what bothers me most..
what do you think? is changing the question worth a try?