With this program (whose name I ironically cannot write here), Penn and Teller have set out to make a no-nonsense, cut-straight-to-the-facts sort of exposé program. They make no attempt to be subtle or "nice", and anyone who they believe is full of bull gets more than their fair share of abuse. This would be all good and well, if what the hosts were presenting were actually facts. Unfortunately, what they do present are opinions, ones that are sometimes based on the truth, and sometimes aren't. Their approach to the world is a backward one - they choose a stance on a subject and then seek ways to validate it.
Though Penn and Teller seem to want to align themselves with empirical science and skeptical intellectualism, they are in fact attacking those very values with their prejudiced and opinionated approach. They ignore the accepted notion of science not being about seeking the "facts" and experts to corroborate a pre-set conclusion, but rather investigating phenomena and forming conclusions upon observations.
Take the second-hand smoking episode, in which Penn and Teller argued that second-hand smoking isn't harmful and therefore smoking should not be banned in public areas. Scientific research clearly indicates that second-hand smoking is in fact harmful - a fact that completely undermines their argument. Another episode where they choose opinion over science is the obesity episode, where they assert that obesity is not really a health problem, but a ruse by pharmaceutical companies who seek to make money off of dietary medicines. However, scientific data implicates obesity as a serious threat to public health that claims millions of lives each year through associated illnesses.
There are, of course, episodes where they hit the nail on the head, with the viewer being left with an almost guilty feeling of content as Teller's voice-over spits out insults at greedy moneymakers who are out just to exploit and make a buck off of gullible people. These are the moments where the program shines, but just aren't enough to make for the shortcomings in other episodes. The fact is that it is hard to take anything Penn and Teller propose seriously when they've let down the ideal of scientific fairness and objectivity on several occasions.