If you saw the lights-on portion of the HK space mountain video, you can see if you look carefully, that there are actually projecting screens set up throughout the ride, to create a surface to project all of that imagery on.
Well, I was always under the impression that Rockit Mountain wouldn't necessarily be as dark as Space Mountain, and that these flat white screens would potentially be visible.
Perhaps I am just searching for excuses.
-Jahan