Yes I agree with your theory.
I absolutely loved the last episode to this series, with all its twists and turns. I know some of you aren't fans of Moriarty, but I think that he's a fantastic villian. In my opinion, Moriarty is the epitome of the classic film/book villian. He matches Sherlock's intelligence, but uses it for evil rather than good. Also I love his arrogance for some reason. I can't wait for series 3!