The main reason it's incorrect is because for a while, people assumed "Darth" was Dark Council only (not sure where that idea came from, but whatever), and even after it became clear that wasn't the case, no one bothered to correct it.
As a side note, while I'm fine with the fact that EVENTUALLY the Republic wins, it bothers me that every single Republic victory has people flogging to defend it with "The Republic wins anyway, so shut up".
I mean, how are we supposed to feel the Empire is any way a threat to ANYONE if they lose in every book they're featured in? Especially when the Empire's few victories are swept under the rug, like the examples in this thread.
As a Sith/Imperial fan, this is most disheartening.
Exactly, lets just say I think the empire is going to lose even more stuff since the new lead writer was one of the main writers for JK and smuggler.