Brian
Its clear we are thinking in different ways.  Let me be more precise.
When I brought up the subject of running or other such tests, I was referring to the idea that such tests could be video taped to preclude abuse, not as a direct comparision to polygraph.
You see, if you piss off the person timing the run for whatever reason, perhaps he might add a few seconds if your close, or downgrade an interview score without cause.  I thought the idea of videotaping was to prevent abuse, was I mistaken?
I certainly did work in the federal system as an agent, and also took and and passed the USSS polygraph (a job I did not take).  I left the Federal system and for personal reasons (like spending time with my family, and not getting a divorce) I went into local law enforcement-where I currently am a detective.
I disagree with your assessment that a failed polygraph is a fatal mark on your record.  Look at Fair Chance's example of how to work within an imperfect system.  Not only has his initial failed polygraph not impacted his current federal position, it has not stopped his current FBI process.
And Brian, I do not know any agency that uses polygraph as the sole hiring criteria.  Regardless of what you read on these pages, I know for fact that what is used is much more of a whole person approach.  Polygraph has however become the lightning rod of the hiring process, and a way to subjectively dismiss an otherwise acceptable applicant as "not within parameters". This is my belief anyway.
And as far as re-testing, an agency should not use the polygraph casually.  If a person fails the drug issue for example, specific re-testing and investigation should occur.  That is only fair to the applicant.

Orolan
When I mentioned something like taping would be cumbersome, you chose to remind me how to turn on a VHS and camera.  I meant it might be impractical in a high volume agency to keep such recordings, and it would be almost out of the question financially to provide a personal video record to each applicant.  We use a time delayed recorder in the 12 hour mode to get about 6-7 tests on one video. See my point?
As far as championing other causes, I would never want anyone to waste excessive time, as some already do here, on further causes.  A simple recognition would be sufficient that human bias, incompetence, arbitrary standards like those contained in some physical tests, certain psychological tests misused for applicant screening...have hurt more than polygraph ever will.  Im sure you get the idea.
Why most working law enforcement officers that need answers dont mind using polygraph is simple.  They have seen it work.  So to be limited by someone who has just failed, and is pissed off, and wants revenge...does'nt sit well.
Personally, I want to request one if I think I need it.

Your zeal will never take the place of my experience.