uh, I think you missed my point. The reason that you get your background checked so thoroughly is because you're going to be a target of the bad guy's humint (so that he can use your access to cryptosystems for sigint), so the good guys vet you first to find the skeletons in your closet. This is most definately offensive humint.

That's an interesting point. If piece of information X is easy to verify, then so is piece of information Y where Y is some blackmail material on an individual who knows X. That does make sense.