I think it's an interesting scene and I find it odd it's not leaked until now. I don't doubt it's authenticity, just impressed. It's weird though - as I watched it, I felt as though I have seen it before (don't know when or where), then start wondering if it's because I've read those lines of dialogue - actually, it's probably at least mentioned in "Returning To Jedi" documentary, perhaps with some stills?

It was quite an emotive scene, I did like it in isolation. Maybe in the film it did break the flow and spoil some surprises. After all, Luke still turns up all hooded and mysterious as Jabba's palace and does some force choke which is pretty dark side.

Also, about recycling footage - at the end of Jedi when the death star is falling apart and Luke is escaping with Vader the TIE Pilots running around are out-takes from the first movie.