It's always nice when readers see more than I thought was there. I never even thought of Coventry in connection with Scandal, or the Bart's scene. :)
I think John needs to learn to trust Sherlock, and Sherlock needs to learn that emotions and friendship can't be gained through trickery and manipulation. As we only really see Sherlock's view in this, it's sometimes easy to forget that they are both pretty dysfunctional, when it comes down to it.