Marc, Fred, Rodney & Ben, thanks for your comments and contributing to an interesting discussion about ethics/techniques and these new trends in post processing.
Ive loaded a comparison image here, where you can see the starless 7hr Ha stack before (right) and after Topaz NR (left). Previously in my workflow I used Topaz NR sparingly at the very end of the process, but in this case I used it on each stack prior to assembling the image.
I'm not sure if I can agree though, that the Ai is introducing something that isn't there, rather in the style of a scene from the original "Blade Runner" movie, it's enhancing what's there already.
(with the exception of two artifacts at 10 and 11 o'clock that resemble dustlanes, I could have softened/blurred these but I chose not to for the sake of the exercise.)
As I mentioned though, otherwise I've used it sparingly, it is indeed possible to push this technique further, and that's when Marc's observations certainly ring true.
PS: Welcome back Fred, I found your image of this to be very interesting when researching this target.