The EMT (or EMH) is obviously false in its strongest form. However in a weaker form it is generally accepted even by behavioral finance guys. That is, even many (most?) behavioral finance economists believe market is efficient enough that investors should not expect to outperform the market. Can read a little more and get specific example of behavioral finance guru Daniel Kahneman on this point in Wikipedia article here: http://en.wikipedia.org/wiki/Efficient-market_hypothesis