Ritchieverse Moriarty/Moran

[shes-a-geek.livejournal.com]

I'm looking for a M/M fic I read shortly after A Game of Shadows came out. It followed Moriarty and Moran through their first meeting until just before Reichenbach, and I believe I read it on either LJ or tumblr. The main thing I remember was, after Moriarty decides to hire Moran, the colonel (not yet realizing the extent of Moriarty's activities and wondering why a mathematician would hire him) makes a comment about how "those equations are tricky bastards" or some such thing. And Moran pictures himself taking notes at Moriarty's lectures.

There are a lot of references to mathematics and Moran trying to understand how Moriarty works. And it was awesome, and one of the first AGoS fics I saw. Sadly, however, I forgot to bookmark it. Anyone else remember it?  Thanks!