I wonder where they come up with those techniques. From what I know the techniques used in the movies were derived from medieval sword techniques and in the three prequels some of the techniques were from Kendo. I do know David Prowse, the guy who was Darth Vader had been a fencer.
Bob Anderson taught most of them how to fence, and 'created' the duels themselves, I believe, for the original three. He did that for a lot of movies with rather good swordplay though, so thats nothing special. No idea if he was involved in prequels, but probably not if they used kendo instead of fencing.