I agree with everything you, just, said. Except Darth Vader Purging the Jedi, he didn't do it alone. But he was in charge and leading the Clone Battalion of the 501st Division. He did take out Cin Drallig, the saber instructor (Nick Gillard, the stunt coordinator, backwards?), and his Apprentice in both the Video Game and the Movie. So, he definitely had some skill with a lightsaber blade.
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