It would be really interesting if Lucas was being dishonest about his edits at that point in time. Rather than just having let his fame and fortune go to his head, it would really paint him to be more the pathological liar. And no one would have really judged him or cared, at the time, if he had made changes to THX. If he was trying to convince anyone, it was himself. Which is interesting to keep in mind when listening to him in cases like the SW blu-ray commentary, where almost every sentence out of him is a justification of some sort. I always assumed those justifications were aimed at the audiences, but perhaps it’s for himself as well.