But, for example, if they would run a query "select everyone who uses email encryption", and then analyze this subset of people further, then you might have pla

But, for example, if they would run a query "select everyone who uses email encryption", and then analyze this subset of people further, then you might have placed yourself under radar, and they can have a closer look at your other non-encrypted traffic. Basically, you revealed that you "have something to hide". Anyway, I have found that if some article claims that you should or should not do something to protect yourself against NSA, it is almost always written by an amateur. The real experts know that we currently don't know which capabilities NSA has and what exactly they do, so it is almost impossible to assess if something will help or not help or hurt. My "amateur gut feeling" tells me that if you really want to send something secretly, you should at minimum setup a separate hardware+software with no connection point to your real identity. But this is not advice against NSA, just an opinion.