I would argue with this one point. The theatrical releases are not always director's preferred versions. Most directors do not have final cut on their films, they are bound by contracts to fulfill certain obligations to the studio, and often the ratings board demands that content be removed to get a desired rating. So most directors do not have complete control over what version of the film is released in theaters. In some cases studios have allowed directors to go back and create a new version of the film that, presumably, they would have preferred in the first place. That may include restoring content that was removed to accommodate the ratings board or to accommodate an annoying studio executive, or just having second thoughts about something. Peter Jackson shots hours of additional footage to create his Extended Editions of LOTR - even though he says he prefers the Theatrical Cuts (I think he's wrong about that!) As you point out, Ridley Scott prefers the Theatrical cut of "Alien," but not "Blade Runner." (Incidentally, the two cuts of "Alien" are nearly identical in length, so he not only inserted that missing scene of Ridley discovering the hive into the extended version, but removed content as well.) So which is the "definitive" version really depends on each individual case. Worth paying attention, I suppose, to whether it's called a Director's Cut or an Extended Cut. That may give us a clue as to the director's preferences. But sometimes directors are wrong!