Psychologists may be able to itemise all of the different ways in which our minds play tricks on us and lead us to poor decisions (remember Mrs Clinton's "miss-speak", her husbands denial or Mr Blair's 40 minute claim). Evidently the greatest political minds make astonishing mistakes. Undoubtedly, some of the population are more fallible than others, but does this undermine our ability to make good collective decisions in Interactive Democracy?
It may be that in some circumstances taking a measure of the choices of a large diverse population is less susceptible to brain error than in a small integrated population like the House of Commons where social pressures may contribute to bad decisions. To some extent this is detailed in "The Lucifer Effect" by Philip Zimbardo and James Surowiecki's altogether different book, "The Wisdom of Crowds".