So it got me thinking - what if Luke revisits the cave on Dagobah in ROTJ? Could this be a place for a flashback, a foreboding prediction of later events in ROTJ or a teasing link to the ST? How could this work in context to PT or ST edits that might decide to cut or change events slightly?

Oh I like that. I can’t currently think of any use for it but it’s nice to know the option’s there. Then again, the Dark Side Cave is supposed to be a test, not a revelation.

Anyway, point is, I think the Empire regrouping works best as the second-to-last scene the film that our protagonists are unaware of. Basically what Rogue Leader said.