I’ve not read right back down the thread for a while so I can’t remember the specifics, but I thought he was going with the idea of Dooku being a Sith… However, I admit I don’t know the mythology (for the prequels, at least) well enough to know whether that validates force lightning in itself?
I certainly didn’t have a problem with him using it, even though Plap’s other boys never saw the need… Maul was more of a swordsman, and Vader was more of a sliced up despot who controlled through force of will and, er, THE force. I felt the variety of the apprentices and their abilities gave the three new films a bit more interest than they might have had.