I very much agree with that line of thought, MyNameDidntFit.
But the idea of some class along those lines had also been brewing in my mind. It seems indeed very thinkable that Sith would have some deceving, hidden, sneaky class. It would fit very well in the logic of them being generally evil and deceiving.
Also, it accomodates the idea of Trooper vs. Bounty Hunter, and in the light of this, Smuggler vs. "Spy" (or what you choose to call this class).