A good summary of the key points from the literature. However it is possible to placebo-test CBT; we did it recently for our web-based CBTi programme sleepio.com. The paper's been accepted for publication by the journal SLEEP - read it here: http://www.journalsleep.org/AcceptedPapers/SP-025-12.pdf

Also check out the lengths we went to to develop a credible placebo here: http://www.sleepio.com/research. Basically a complete bogus system, with new tools, animation, voiceover and library...