yes, interesting. And Redbeard does have to mean something - especially after Gatiss's tweet!
But I keep thinking that, if the whole thing was so dangerous, and also so clear and known to Mycroft and Sherlock, why the heck would they not do anything about it?
To me, it seems Sherlock has overlooked things, and this is weird. Yes, he is involved, but he is Sherlock...and ultimately, he wants to make sure John is safe, and by overlooking things he is instead ensuring pain for him... weird.