I had a similar moment the other night, while playing Star Wars: the Old Republic.
Bioware seems to have disconnected Light Side/Dark Side from Jedi/Sith. You can earn Light Side points as a Sith. You can earn Dark Side points as a Jedi. Being a Roleplaying geek, this immediately reminded me of the old AD&D alignment system.
Jedi/Sith = Law/Chaos
Light/Dark = Good/Evil.
YMMV, but it's an interesting idea if I ever run a RPG in the Star Wars universe again.