Well if he really wants to blame somebody, he should blame the pension funds. They were the ones who were buying up the storm towards the end of the year. The market was at a nice all-time low and those pension funds had to go in and put in the buy orders and that propped up the market.
I don't think Einhorn is wrong with his shorts choices quite honestly. It's just that he's shorting them way too early. Unless there is an overnight disaster happening to a company, it can take a long time for a company's stock to adjust to its "true" value from its seemingly inflated value.