I don't think they mention that in the film proper, but it is discussed during the Q&A bonus feature.
Eyes Wide Shut is one of my very favorite Kubrick films, so I am naturally looking forward to that documentary!
Simon, in that case, I think you'll love this movie. It turns out in this case, "assistant" meant that he was assisting in pretty much all aspects of production. It was Vitali, for instance, who discovered Danny Lloyd for The Shining, and who also worked as R. Lee Ermey's acting coach on Full...
This is absolutely essential viewing for all Kubrick fans. I’m truly delighted that I got to be the reviewer for this one.
Don’t let the fact that it’s DVD-only dissuade you from checking it out!