Polygraphs are one reason I left classified work for greener pastures. I believe they are nearly worthless, used just as much to harass as anything else.
In my last classified job, my employer hired a new security officer. After several months on the job she was sent for her polygraph. She returned the same day, the test unadministered because she had a heart problem. The problem was manageable, but it made it impossible for an "accurate" test. Despite this she remained in her job. With access to far more material than myself and others--sensitive material covering many programs--she was excused. Obviously the intelligence community doesn't believe in polygraphs either. I'm glad to be out of that world.
I attended the first ApacheCon in 1998. One of the top brass at Yahoo (founder? CEO?) spoke on open source software. I don't recall all the details, but I remember him saying that they had about 450 servers running BSD.
During the Q&A, someone asked what version of BSD they were running. As I recall he said that over half were running the latest, another 30% or so were on one version earlier, and the rest--15-20%--were on an older version. This caused a mummer from the audience, and an ASF panelist asked for elaboration.
Oh, replied they Yahooligan, why the old OS? Well it doesn't seem to make much sense to reboot a server that's run for over 18 months without a problem just to upgrade the OS.
At this point the president of the ASF, Brian Behlendorf, stepped to the mic and said, "Let's hear Microsoft say that
The crowd went wild (except for the two MS reps in front of me).
The rule on staying alive as a program manager is to give 'em a number or give 'em a date, but never give 'em both at once.