Microsoft appears to be pushing people away from NtClose.
I'd suggest you to find a reason why.
That particular documentation happens to be part of the API released under court order. They didn't want to give it out to begin with, and they don't want people using it now.
Perhaps someone should determine if there are any applications statically linking to any of those functions, which would disprove the claim "There is no import library, you must use GetProcAddress" and leave MS in violation of said order.