Please post links, then quote out the relevant parts. This way if someone wants to they can go read the full article.

I don't think the Lucas/Kurtz rift was as abrupt as you make it out to be. From the Making of ESB book, you get the sense that both Lucas and Kurtz felt that for ESB to be successful that they needed to up the quality, so Kurtz continued with that throughout production, while Lucas was watching his own bank account dwindle and came to the conclusion that Kurtz was giving the production team too much leeway. This is one aspect which became a rift. And along this way, the two of them are planning out the other episodes, don't know when Kurtz exactly left LFL camp, was it prior to the first RotJ script or somewhere during pre-production? So when Kurtz talks about what he thought RotJ was going to be (Luke going off into the sunset for instance) when this idea was briefed would be interesting to speculate on.