Thats a very interesting way of putting it. But why do you trust your doctor or psychiatrist?

I would argue that we "know" Bruce Schneier from his writings and his works better than we know our doctors. The reason we "trust" our doctors is the implied and understood restrictions on sharing confidential medical data and not the character or works of the individuals (since we don't really know them).

With the NSA, that implied restriction (Constitution, laws) has been breached.