In this episode, when Sherlock explains to Anderson his supposedly true story of how he survived the Fall and faked his death, he said that not only was Mycroft in on it, but they'd both been planning essentially this from the beginning, attempting to destroy Moriarty. Sherlock was apparently in the know about Mycroft feeding information to Moriarty while he was in custody. I don't believe him.

here's why. This is the clip where John confronts Mycroft about who gave Moriarty the scoop on Sherlock. http://www.youtube.com/watch?v=1CamZyd2iXs&feature=player_detailpage

When John's leaving, Mycroft has an expression some what akin to remorse, and tells John he's sorry, asking for the message to be passed along. For Mycroft, this is strange, which would almost lead me to believe he's acting. But what's the point? John didn't expect Mycroft to be sorry, he wasn't looking to hear that, and he wouldn't have believed that Sherlock knew about the information leak unless Sherlock told him, so there's no need for Mycroft to pretend anything. Therefore, I believe it's real remorse. As I've written this up and thought about it, however, I've come up with two counter-arguements.

For one: Mycroft's remorse is real, but not for the reason he suggests. He is sorry for what his brother is going to go through, in part because of him, though he actually had his brother's consent. It's a lesser evil that he's committing, but still bad enough that a person might naturally feel remorse. However, Mycroft is not a normal person, and from the things he says and does, I'm not convinced he cares so much and so openly about his brother to apologize for causing what would seem, compared to utter betrayal and possible death, like a mere disomfort.

The other arguement: Mycroft intends to pass a message in code, hidden in that apology. Okay, but I highly doubt John told Sherlock what his brother had said, and Mycroft would've known John well enough to make the same deduction. Also, he could just phone him. On his phone. (Sorry.)

So I think what Sherlock told Anderson about having Mycroft feed Moriarty information is probably bull. Thoughts?

PS: The Sign of Three and His Last Vow don't exist until everyone on this thread has seen them. No spoilers, please.