By John RumseyLuis Stuhlberger, Brazil's leading hedge fund manager, is a constant fidgeter. In his office in São Paulo, he flits among the pile of papers in front of him, takes short calls on his cell phone and interrupts other team members to contradict or refine their views. But the result of all this restless energy is a nimble, contrarian investment strategy. "If you look, there's no one doing exactly what I do," says the 55-year-old Stuhlberger, whose unruly hair, dark eyes and ability to talk 19 to the dozen mirror the firm's intensity. "I feel like I'm sailing alone in my own particular ocean. And that's a good feeling."Like Brazil, which is enjoying its long-awaited moment in the sun as host of the 2016 Olympics and with a red-hot stock market, Stuhlberger is on a winning streak. As head of asset management at Credit Suisse Hedging-Griffo, a leading Brazilian...