[quote=Alexander]like this:
I think I remember hearing that the reason Vader has to live on life support and the reasons he's lost arms and legs and whatnot, was a fight he had with the emperor after which he gave in to him.
however in this part we see him have a fight with Obi and that being the reason for his situation.
that's actually what I mean. hope it makes more sense now

[/quote]
In an ancient interview dated more than 20 years, Lucas claimed that Anakin's body was destroyed after the fight with Obi-Wan. Apparently, he had "fallen into a volcano".
In the initial Episode 3 script, from 1983, Anakin once again fights Obi-Wan, and his body is destroyed.
Haven't got a clue where you got that from.