Picasso - All prints of paintings done by Picasso are edits. Every poster or "museum quality" copy is a cleaned up version of the original. Colour-correction, despeckle, and etc were done to make it look better because artifacts were introduced during the duplication procedure. Lest we not forget that restoration is also done to the originals for the sake of perserving them. En total, however, I do not feel that Picasso is a fitting example for this argument because ...
if I control a Picasso I can
...as far as I know, no person on this board has an original print, or even a duplicate of the original film print. We do not control a Lucas, and have no ability to alter a Lucas. We each have in possession a copy or two or three of a mass-produced reproduction. Barring inflated prices on eBay, these mass-produced reproductions are worthless in the grand scheme of the art & film world.
All in all, I think it is safe to assume that none of us control anything of substatial value that would facilitate or deny a Star Wars film archival project of import.