Some parts would be easy, like removing the Jabba and Han scene from ANH, others may be harder.
The biggest problem would be parts where new scenes would be removed and original scenes would need to be inserted, like han and greedo in the cantina. Sure you could just cut in maybe 1 second of film at the bit where the actual shot takes place, but would the difference in quality make it look horrible when you do this? Also on the lines of quality you'd probably need to redub the stromtrooper's and bobba's voices with the 5.1 soundtrack from the anamorphic dvds.
Now I'm not very good at editing myself so I could be way off on this, but if it's possible with decent results then we can have all the benefits of the cleaned up video, sound and effects without the horrible changes.
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I was just thinking maybe I could actually do this myself.
After the official DVDs come out maybe I will buy them, to do this. There's still the problem with parts of lower quality standing out however, and I haven't yet seen the quality of the bootleg dvds (however I hope to soon), so I'm not sure how pronounced it will be.
The main idea I'm having is to make a sort of hybrid between the 3 different versions. Basically keep the cleaned up picture and sound quality, and the better effects (like CG ships and improved lightsabers), but remove the horrible changes like Han shooting first and the Han and Jabba scene.
However I think I'll keep some things from the SE, like the new wampa scene.
A definite change would be when R2 is eaten on Dagobah, Luke says "You're lucky you don't taste very good", which I think is better than in the SE where he says "You're lucky to get out of there."