That's precisely the official thinking about polygraph policy. Ten years ago, a senior instructor at the federal polygraph school floated the idea of criminalizing the public dissemination of information about polygraph countermeasures. I never thought it would come to pass, but it seems a considerable effort is being made.
I'm a co-founder of AntiPolygraph.org (we suggest using Tor to access the site) a non-profit, public interest website dedicated to exposing and ending waste, fraud, and abuse associated with the use of lie detectors. We offer a free e-book, The Lie Behind the Lie Detector (1 mb PDF) that explains how to pass a polygraph (whether or not one is telling the truth). We make this information available not to help liars beat the system, but to provide truthful people with a means of protecting themselves against the high risk of a false positive outcome. As McClatchy reported last week, I received suspicious e-mails earlier this year that seemed like an attempted entrapment.
Rather than trying to criminalize teaching people how to pass a polygraph, isn't it time our government re-evaluated its reliance on the pseudoscience of polygraphy?"