'Sherlock-The Reichenbach Fall' Theory

Part 1-Too Easy

What I have realized is that there is more than one right answer to how Sherlock managed to fool everyone.  However, there can only be one, and that will be explained to us when Season 3 airs.  In the meantime, we can speculate and see how close we get.  There are several parts that drive the machine of this episode: IOU, Richard Brook, Mycroft, and many other factors.

Let's begin with recounting just how the scene on the rooftop went (If you want, you can skip this part.  Actually, you can skip this whole theory, but what's the point of that?).  Sherlock invites Moriarty on the roof after discovering what the lines of computer code are.  Moriarty compliments his choice of a tall building, since he wants Sherlock to jump to his death, and tells him that there is no key code; it was all made up.  Moriarty actually gets very angry with Sherlock, calling him 'ordinary' and a 'doofus'.  After that, Sherlock refuses to jump and nearly pushes Moriarty off instead, until Moriarty reveals that there are three assassins after three of Sherlock's friends (John, Mrs. Hudson, and Lestrade).  Sherlock then realizes that he must jump in order to save his friends, since Moriarty won't call it off.  He stands on the ledge and asks for a moment of privacy.  You think that Moriarty has won, until you hear Sherlock laugh.  He goes back to Moriarty and guesses that there is a recall code or word so that it is possible to call off the assassins.  In other words, Sherlock doesn't have to die if he's got Moriarty.  Sherlock then says that he is Moriarty (figuratively speaking), to which Moriarty replies that Sherlock is ordinary and "on the side of the angels".  Sherlock replies, "Oh, I may be on the side of the angels, but don't think for one second that I am one of them" (favorite line in the entire series!).  Moriarty considers this, thanking Sherlock and saying that he is not ordinary.  After that, he shoots himself, leaving Sherlock with one option:  jumping off the roof.

That scene alone leaves us with many questions, but I think that the most important two are "Why is  Sherlock getting everything wrong?" and "Why is Moriarty so upset with Sherlock for getting everything wrong?"  

I think the latter of these two questions is more easily answered.  Moriarty and Sherlock are a perfect match for each other.  Shelock will always keep Moriarty in check, while Moriarty will always keep Sherlock busy.  However, Moriarty's key code is fake-something that Sherlock doesn't seem to realize.  If Moriarty has, in fact, beaten Sherlock, then they are not the perfect match, and therefore, Moirarty has nothing to keep himself in check.  This upsets Moirarty because suddenly, the world is too easy for him.  If not even Sherlock Holmes can beat him, then there is nobody who can.  That's not supposed to happen, so when it does, Moirarty gets angry.

Sherlock, however, is a different matter entirely.  He never gets anything wrong, and yet on the rooftop, he misses his mark again and again.  This leads to a new question:  "Is Sherlock really wrong, or is he faking it to mess with Moriarty?"  In addition, it has been hinted that the clue for how Sherlock accomplished faking his death was put in an "off-color moment".  Being wrong is very off-color for Sherlock, so maybe this is the place to look.

This brings us to the issue of Richard Brook.  Only after Sherlock says, "I can kill Rich Brook and bring back Jim Moriarty" does Moriarty actually get upset.  This leads us to believe that Sherlock is wrong here, but about what?  Moriarty seems to think that it is about the code, but what if it is about Moriarty himself?  Think about it.  If Moriarty operates under his real name, you would think that his name would be well-known as a criminal, like Bonnie and Clyde or Al Capone.  However, it is not.  Rich Brook, on the other hand, is a storyteller on kid's TV and an actor.  You'd think that Brook would be more recognizable.  If you Googled his name, you would have all sorts of resources on him, but not Moriarty, especially since Brook's records state that he's and award-winning actor.  So what if, instead of Sherlock inventing Moriarty as everyone seems to believe, Brook invented Moriarty?  If Moriarty (erm, Brook) is such a genius, then why would he use his own name?  It makes more sense that he had an alias.

Sherlock, however, knows this.  How?  Take a look back at the final episode of Season 1, "The Great Game".  The second person who Moriarty plants a bomb on, the man in the tan jacket, holds the answer (he is pictured on the side).  While Sherlock is talking to him, he mentions that "the clue's in the name-Janus Cars".  Janus, in case you didn't know, is the god with two faces (in an unrelated topic, January is named after him).  Sherlock would have guessed that Moriarty had a false identity just from that (two faces-two names).

By now you may be asking, "How does this explain how Sherlock survived?"  Really, it doesn't.  It does, however, explain how Sherlock beat Moriarty.  Read on to see how Sherlock survived the fall and fooled everyone into believing him.

*Note: People have wondered whether or not Moriarty faked his demise as well, so why not answer that question here as well?  Personally, I don't see how Moriarty could have faked his death.  He shot himself in the back of the head; even if it was a blank round, he wouldn't have survived.  There are psychological reasons for why he killed himself in addition.  For example, if Sherlock and Moriarty weren't a perfect match, life would be too easy for Moriarty.  There would be no reason for him to live if he could outsmart everybody, even the legendary Sherlock Holmes.  He mentions this at the beginning of the rooftop scene, when his ringtone is playing.  He comments on how staying alive was boring and how it is really just 'staying'.  Who knows, maybe the final problem is staying alive for Jim Moriarty.