[LanPB01]

Here's my bold prediction based on nothing but pure speculation - Palpatine really doesn't know that the spirit of a Sith Lord resides within him. That's why (in Return of the Jedi), The Emperor keeps taunting Luke and demanding that he strike him down. Once free of Palpatine's body, the Sith spirit would then inhabit Luke, who's anger and rage has just pushed him over to the dark side.

[discostu]

We have of course all read the cool ghost body interpretation of the first trilogy http://www.brunching.com/lukeside.html

IMHO Lor was onto more than he jokingly admits. It's clear that Palpatine wanted to die in front of Luke, so the whole Sith Lord possession thing you laid out might not be too far off the mark, but probably not unknowing. Darth apparently knew too which is why he chucked the Emperor down the big hole.

Luke's temptation to the Dark Side would (IMHO) really blow if he gave in. Too much like father like son, he needs to rise above it. It would be cool to see like Uncle Owen's real kid come in as a Sith heavy though.