When Fidelity Investments issued a report on 401(k) performance for 2008, most media accounts focused in on the obvious: we all got creamed last year. The investment giant's "State of the 401(k)" report--reflecting returns for more than 11 million workplace retirement savers--showed that the average account balance dropped 27 percent compared with 2007, to an average of $50,200. But it was something else in the report that amazed me: investors are standing by their 401(k) accounts through the worst bear market in decades.