The New York Times talked to the author of the study, Brent Scott, assistant professor of management at Michigan State University, and he said faking happiness not only worsens moods but also decreases productivity at work. His team followed around bus drivers for two weeks, because their jobs require courteousness while dealing with many, often uncourteous, people. When drivers forced smiles, their moods and productivity declined, but when they were asked to cultivate the smile from a more authentic place (i.e. pleasant thoughts and memories), their mood and productivity increased.
So while forced smiles may lead to a dead end, it sounds like happy thoughts are still in?