Plus it makes Luke’s rejoining the rebels during the briefing difficult to handle.
And I say that as a proponent of the idea.
The other problem is, you can’t really break up the stuff on Dagobah. It’s really just two scenes, talking with Yoda and then talking with Ben. But it doesn’t make sense to cut away after Yoda’s death because if you want to cut back later to the scene with Ben, you’d end up wondering “well what has Luke being doing hanging out at this dead guy’s house?”
I’ve seen the idea knocked around to somehow do a background replacement and make the Obi-Wan scene take place on Tatooine/in Obi-Wan’s hut, but that seems…difficult to pull off at best.
I’ve played around with it before, I think it’s doable. But it would require a few completely new background mattes, as some of the shots don’t quite match up. Getting it to look right would be real tricky.
A couple rough quick concepts I made a while back:
Once I find the time to work on my own ROTJ edit, I’ll definitely try my hand it piecing this scene together. I’ve always loved the idea.