By Richard SchmittNEW YORK ( TheStreet) -- "The times, they are a-changin'," Bob Dylan once warbled. Although unlikely, Dylan could very well have been referring to changes in market conditions that should prompt a new look at traditional retirement savings investment strategies. To savvy investors tired of languishing returns of late, perhaps his lyrics could serve to underscore the market's message: move over, buy-and-hold investors; there is a new sheriff in town, and he is 401(k) daytrading. Conventional wisdom once suggested holding stocks for the long term. After all, the broad stock market rewarded buy-and-hold investors with generous returns in the range of 11% per year on average from 1926 through 2000. It seems investors got used to the powerful engine of economic growth driving outsized market returns over the long term.