darklordoftech said:

...They also say that users of the dark side of The Force who aren't called "Sith" will confuse non-fans, a claim so rediculous that I don't know what to say.

I always thought that bad-guy force-user = sith. So a bad-guy who uses the force would be a sith to me. So, yeah, I can see it being confusing... except that I can't see how it would matter to the story or to anybody that the bad guy using the force isn't actually a "sith" (whatever that even means). It's like a christian being a Baptist or a Pentecostal. The denominational differences probably means much to the individual, but it's all Christianity to a heathen like me.