Skeptic,

You write in part:


Quote:

There are at least two devastating arguments against the "security through obscurity" principle.  The first is that details almost always come out one way or another.  The second is that more scrutiny leads to the plugging of holes in security, not to its compromise.

You make an astute observation here. With regard to polygraphy, for example, note that during the Cold War at least one U.S. Government polygrapher defected to the Communists. Retired CIA polygrapher John F. Sullivan mentions this at p. 235 of his book, Of Spies and Lies: A CIA Lie Detector Remembers Vietnam (University Press of Kansas, 2002):


Quote:

During my tour with the [U.S. Army] 513th Military Intelligence Group in Germany from January 1965 until July 1967, one of our polygraph examiners, S. Sgt. Glen Rohrer, defected to Czechoslovakia. While investigating his defection, we learned that the Czechs ran a polygraph countermeasures program and that the head of that program was a Dr. Miroslav Dufek.

Presumably, anything of importance that Glen Rohrer knew about polygraphy also became known to Eastern Bloc intelligence services (if it was not already known to them).