It wouldn't have worked, anyway. One of ROTJ's flaws is that even if the Emperor/Darth had turned Luke, they would all have died when the Death Star II blew. There was no direct link made between Luke's victory and the triumph of the Rebellion- Vader and the Emperor would have died anyway. So despite those scenes (Luke, Emperor and Vader) being the best in ROTJ, they ring rather hollow.
I don't see how he could have stopped them. His whole plan hinged on the deflector shield generator being up, based on his (insanely dubious) assertion that a legion of stormtoopers would hold down below. That's the whole problem with the Emperor as presented in ROTJ... his plan was a load of crud. Master of the Force, my backside!
Actually, it happened before that. There's a theory that Palpy was so caught up in either the battle between Luke and Vader (working on Luke to turn) and in destroying him that he no longer held is strong Force control over his troops and that things went bad because of that. It's a bit cheesy but it fits here as a piece for the debate.
Well if you want to pick nits, if Leia hadn't pulled out that blaster between her and Han after she got shot, they probably never would have gotten another chance to blow up the shield generator.
As far as what was happening on the death star....if it had all played out as it did in the film, Luke might have not gotten off the death star as easily as he did since the imperials would not have been a mad rush to evacuate. If Luke had turned, it would have depended if he had destroyed Vader or not as to what path the story would have taken. It was a logical end and provided closure to the OT, even if it wasn't quite what SOME of us wanted. 😈
The ending vis a vis Luke;s joutrney is fine, I have no problems with that. But the Emperor's aura of menace is ruined by the crapness of his plan. Hell, even with the DSII operational, the Rebels seemed to be unaccountably doing better in the battle! It had no contingency for things not working out, which is hardly what you expect from one so strong.
I have a feeling it actually worked out like that on film because all the different story threads were so seperated. GL probably didn't intend for the Emperor showdown to seem so seperate.
Well the rebs got the super star destroyer by sheer luck, and it made a hell of an impact crashing in to death star.
If Luke had been killed , they, palpy and vader, might have fled the space station. They knew if the deflector shield got knocked out there was a big chance death star would be lost, but the imperial fleet would have thorn the rebs appart ship by ship in the end.
I agree with Ush though, the emperor based all on the legion would win the battle on Endor. Bad move he should have other alternatives.