Well, the guy you talked to who worked in that book store, said there was the '76 release (I assume this is what we have preserved) and an Italian re-release in '78 or '79, I just thought it would be interesting if it is the re-release version, and if it is, I would guess it was treated with a new dub with all the additional scenes and audio work needed for that cut?

That your 16mm print contains "the lost SEN scene" is still a big mystery to me when everything else in that print match the regular home video version. But when it comes to the tinkerer Lucas it wouldn't actually surprise me if he cut that scene differently when it was time for the video release in '82. It wouldn't be that weird if people didn't take notice or document it if he shortened that little scene a few years after its '78 re-release. I like it but the longer conversation is not exactly an necessary inclusion, in the end it must have been Lucas himself who decided to cut it for some reason as it was probably left in by WB in '71 and as we know, it was also in the Italian release.