SKot said:In the early ROTJ trailers, Luke's lightsaber was not green...it was blue. It was colored green later.

That is an interesting can of worms, but if Nerfherder's earlier quotation can be relied upon, and I think it can, and this was cut from the final cut during post production, then the trailers might well have been completed before then. There is that shot in the ESB trailer with Artoo during the escape from Cloud City that did not have the laser blast effects added in, which shows that that trailer was made before all the effects were complete. In the ROTJ lightsaber scene the effects are present, so perhaps the ROTJ trailer had already been made.