I think it has to be evaluated on a case-by-case basis. Peter Jackson's extended cuts are going to be a different animal from James Cameron's 'special editions' of his films, which are in turn a different animal from any director's cut of one of Ridley Scott's films. Not to mention Lucas' SW special editions are a different animal from all of the above. Not only do various terms for these things get tossed around, but different directors are going to have different ideas about what exactly these things do and what their objective is.
The most obvious example of this is with the Alien films, as each one of the alternate versions of these films has a different agenda.
The special edition of
ALIENS was created first. James Cameron has gone on record saying it was his preferred version of the film (sounds like it may as well have been called a director's cut). For a time (1999-2003), it actually replaced the original as the only version available. There are arguments both for and against this version. In my own opinion an 'ideal' cut of the movie would probably fall somewhere between the two existing versions (which is how I feel about most of James Cameron's movies). But I'm not James Cameron. For
The Abyss, I think one could definitely make a case for the theatrical version as being inferior. But again, I also think the special edition restores too much.
Moving on, we have the director's cut of
A L I E N. Again the term 'director's cut' here seems a little presumptuous, as it is my understanding that Scott mostly made this version for the 2003
Quadrilogy set because the studio was prepared to do it anyway. It got a limited theatrical release though, which seems to lend it some additional legitimacy. This version is actually shorter than the original, as Scott felt strongly about it being a different experience rather than just a longer cut of the film (the studio probably would have inserted all 12 minutes of deleted scenes, just as countless bootleggers had done off of the special edition laserdisc). For me, I think this version's biggest contribution was that it gave the studio an excuse to re-release the film to theaters. The original version seems to be preferred all around.
The
ALIEN 3 'assembly cut' I dare say I think is more educational than anything else. I'm sure some fans might consider it a better version of the film, however I cannot. I wouldn't even consider it a complete version of the film, even after the missing dialogue was restored for the
Anthology release. At the most, I think maybe it's on par with the TV broadcast version of
Dune: you look at it, you see a fuller picture of what the director 'might' have been trying to do with it, and you see the material is there to create an alternate cut of the movie. However the longer version is like a text, blueprint or roadmap; it is not that alternate cut that could have been made, and it is a jumbled version in and of itself. David Fincher declined to participate, so the studio essentially took everything that was available and spliced it together (same thing Scott prevented from happening with his installment).
After buying the
Quadrilogy in '04 and the
Anthology last year, I still have never gotten around to viewing the alternate version of
Resurrection. And it's probably been ten years since I've seen the original for that matter. However it sounds like this is one of those cases where an alternate version was put together simply because they were able to.
Ideally, I do believe that every version of a film should be available just for archival purposes. And I think
Blade Runner is the textbook example of how to handle something like that. If I were in charge of the next
SW BluRay release, I would not stop at restoring the original editions next to the final versions of those films, but I would also reassemble every version known to exist in between (and even some antiquated versions, like the 70mm print of
Empire rumored to have featured a somewhat different edit of the film).
But while I realize it is arrogant of me to assume that people not that taken in with the
Rings movies may have started with the wrong version of the films... I still believe that to have been the case with my co-worker.
