Was it actually someone else’s idea other than George to make changes to the movie (even if it was just re-doing a dozen or so shots with cgi) or were Muren and Knoll simply George’s enablers?
“George said, ‘As long as we’re going to re-release Star Wars, I always wanted to do more in the sequence at Mos Eisley [the metropolitan spaceport of Tatooine] because the town didn’t appear large enough.’ So we went back to expand Mos Eisley, and then to do matte paintings of the Sand Crawler and Jabba the Hutt’s lair. The initial scope of it involved just two dozen shots.” - visual effects producer Tom Kennedy
“I remember first hearing that they were going to re-release the movies in anticipation of the new series of films. A few weeks later, I heard that George was going to add some scenes that he had always wanted to do, and fix some things up. I felt we could improve the matte edges on some shots that had been done at the last minute—particularly those involving explosions. But there were also a number of shots in the space battle where the movements just weren’t right. If we could smooth them out, the action would have more clarity, and viewers would be able to follow the movie a little better. I suggested digitally re-doing shots in which the models were moving incorrectly.” - Dennis Muren
(I started gathering sources for a History of the SE years ago, kind of missed my 20th anniversary deadline, eh?)