I'm not sure of the precise details of her views, having not read any novel where it was elaborated in, but it does sound a lot like the Unifying Force concept. On its wiki page, one appearance listed for it is the book MedStar II: Jedi Healer, starring none other than Barriss Offee. I presume this is where it was elaborated on. The notion that there is no true light or dark side of the Force is also described on this page as being similar to the view of Darth Sidious himself (ie. that the Jedi see the Force as an end while the Sith see it as a means to an end) and also the view in which, in the NJO era, Vergere teaches Jacen Solo. Obviously, these are some dark characters, the last of them coming to grips with this understanding of the Force before eventually falling to the Dark Side. It does appear to be a trend that Jedi who adhere to this view usually turn out "dark" to some degree. Just looking at the list of appearances for the Unifying Force concept, it appears that Barriss was (still is?) an exception to this trend. She does rail against the Dark Side and the Jedi Order's apparent servitude of it, while engaging in "dark" acts for the purpose of the perceived "greater good". A different - possibly more politicised - understanding of light and dark might be the motivation for this. I know that the Unifying Force and its relation to the Dark Side is controversial, but it's just a thought. Can it be said that the mainline Jedi Order itself has also sanctioned some dark deeds? How hard is it to separate Barriss' actions from those sanctioned by the Jedi Order as part of fighting the Separatists? It's fairly easy to see why the Jedi choose to fight - to prevent the Sith and Separatists from conquering the galaxy, in a Naboo crisis writ large - but no-one short of the most fanatical militarists would claim that war is anything but hell. It might be a necessary hell given the alternative, but it's not hard to see why some Jedi would outright reject it. Even putting aside comparisons to Sidious and Jacen Solo, how does Barriss compare to Anakin Skywalker and others? She uses the Force Choke on one occasion to kill a single loose end, while he uses the Force Choke every other TCW episode as a crude intimidation tactic to get his way or the upper hand in the fight. She cold-bloodedly kills clone troopers, Jedi and support personnel for her political goals, which is to some extent similar to what Anakin (and other Jedi) do as well in the course of fighting the war. Just how much of her "darkness" - which she appears to be partially conscious of - is truly exceptional relative to other Jedi?