An interesting counterpoint to this is the concept of the Potentium from the later New Jedi Order books, which flatly states that the light and dark sides just doesn't exist. A few books after this Jacen Solo was introduced to and mastered this philosophy, it was pretty unceremoniously rejected by the Powers That Be (George) but I always liked it. It actually fits rather well with Utena's "I'm pretty passionate but I'm not a fucking sociopath" philosophy from S4.
With all of that said, that's a cool revelation and I'm looking forward to seeing some character or another (Len?) come to it.