The problem is that those BS detectors are tuned to be so sensitive that they tend to register false positives. I.e., 9/11 "truthers", the people who believe Obama's birth certificate is a fraud, etc. The question I ask these people is "what amount of evidence would cause you to change your views?" They'll toss off a few impossible to satisfy conditions or just crank up the crazy. Bottom line is, you're never going to convince these folks that their view is wrong, evidence be damned. Same for the global warming "skeptics". Exactly what amount of evidence will be required to convince the board of Exxon that global warming is a fact?