The Final Problem - How Did Sherlock Fake His Death?

There's just one more thing, one more thing, one more miracle, Sherlock, for me.
Don't. Be.
Dead.

Going by the evidence of Doyle's original story, the final seconds of Sherlock's last episode and that we know season 3 is going to air some when within this millennia starring Benedict Cumberbatch, you don't need to be Sherlock Holmes to deduct that he must have faked his really realistic looking death in "The Reichenbach Fall". So, the more advanced question is how he did do it.

How does one survive jumping from the top of a building? The answer is, you don't. But assuming that it was possible, it might be logical to say that Molly helped him with it. After all, we see him seeking her help. And when you're Sherlock Holmes, that's not something you'd usually do. And being familiar with Moffat's trolling capabilities that's what he may have been pointing at when saying the clue is all there... However, the episode offers us more than this.

First of all,  let's not forget that Sherlock is the one inviting Moriarty to join him on the rooftop. He's the one setting the when and where. Therefore, it's just logical to assume that he did not show up there without making some preparations.

The night before jumping Sherlock is constantly playing with a rubber ball. And given the fact that John only checks Sherlock's wrist and not his neck for pulse, there is the possibility that he used it to create the illusion that his heart stopped beating. (Of course he's doing it right after jumping off a building, which makes this [if this was real] even more remarkable).

But there is even more. We can assume that Sherlock is telling John Moriarty's lie because he does not want John to suffer. He hopes that by implying how much he betrayed him John will terminate their friendship or at least, he will take things more easily. The last time they see each other he makes John mad at him by implying that he does not care about Mrs Hudson having a possibly life-threatening incident, something he has obviously came up with for this very purpose. Sherlock does not gain anything by this, in fact it hurts his own feelings because John's opinion and his friendship are important to him. Sherlock shows when he has to choose between his reputation and John, that John's the winner. Putting the sentimental aspect of this aside, and focusing on the fact that Sherlock is obviously not wanting to hurt him, he nevertheless asks him a rather inappropriate thing to do: to watch him jump. He wants John to keep his eyes on him, while he's falling.

 There may be several reasons for this request, however, the most rational one is that he does not want John to notice what is happening around him. But before going into further detail, let's focus on the location of Sherlock's 'suicide'.

The  hospital from John's point of view

Looking at the two first pictures on the left we learn the building off which Sherlock jumps has 2 floors.

The red-brick building

Just in case you are wondering if that picture shows the right building, it does. The red-brick base is a second building standing between the hospital and John, from where he watches Sherlock jump This becomes more obvious when we take a look at the situation form Sherlock's point of view

And John from Sherlock's point of view.

(picture 3 on the left).

This fact is interesting because we know that the first thing Sherlock tells John on the phone is precise directions where to stand. And Sherlock wants him to stand behind the red brick building which doesn't allow him to see Sherlock hitting the ground. To get to Sherlock he has to go round it and that's when the cyclist runs into him. This means, that John is not really able to see how Sherlock hits the ground. The brick building is simply blocking his view.

Having settled this point there is also the fact that Sherlock's 'fatal' injuries do not match the way he hits the ground.

When falling we know that Sherlock does not flip. The building has only 2 floors and we see both of them in this picture. It is obvious that it will be his feet which will touch the ground first. Not his head, or torso.

Nevertheless, when John finally sees his friend, he has a head injury. How on earth is it possible to get a head injury when falling like that? It simply does not match, i.e. the head injury is not real.

Sherlock's and the truck's position is wrong.

Taking only the rational aspect of this into account he may have got several other injuries, but he certainly does not damage his head, not like that.

The last thing which may, or may not, require an answer is that in the end Sherlock seems to have rotated 9o°C  between falling and hitting the ground. Knowing that he lands 'on his feet', more or less, there is the possibility that when hitting the ground his weight isn't shifted equally and he falls over. However, there should be noted that even if he falls over his feet have already absorbed most of the impact, i.e. when his head finally touches the ground the result is certainly not such a sever looking injury.

Unfortunately, the only thing which cannot be explained away is the distance between the rooftop and the pavement. Because no matter what, Sherlock has to jump. He has to make the killers believe that he takes his life. Sherlock certainly figures out in advance what Moriarty is up to, the whole conversation on the rooftop is mostly a show. This means that Sherlock could have taken preparations to guarantee himself a somewhat softer landing. But he can't risk doing something obvious*. Maybe the fact that when entering the rooftop he's keeping his hands behind his back has something to do with this. And when standing the first time on the edge he asks Moriarty to give him a moment. Does he really need it? Is it part of the show? Or does he use it to do something else?  Besides, I don't think that Sherlock simply needs Molly to give him a rubber ball and to fake an autopsy. She helped him, somehow. And finding out how she helped him performing his magic trick is the reason why I'm looking forward to the next episode. I know Sherlock Holmes wouldn't agree with this, but I think being able to deduct the whole story would leave us with just too many spoilers.

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*Yes, there is that truck packed with some soft-looking washing bags, as we can easily see in the last picture... but wouldn't that be too obvious? Besides, if you're comparing it with this picture you'll notice that the truck is standing wrongly. If it had been standing where Sherlock landed, to get into that position afterwards, the driver would have had to backup. Something he certainly did not, given the fact that it would have been much easier not to back up and to drive away.