C, after Petraeus and his girlie got busted FIVE YEARS AGO using drafts to comm, you don’t think NSA perked up and put some coders on it?
I think NSA had the code before that. Always working on filters to toss totally routine stuff (Farmville).
Huge volume of traffic though, and my hunch is that finding the Petreas practice was not by NSA, it was by looking at HIS or HER network traffic in isolation, using a warrant. There are a few places a trail can start.