As part of Fidel and Raúl Castro's inner circle, Delfín Fernández learned titillating secrets -- everything from why the Cuban leader incinerates his dirty underwear to his cravings for pricey Spanish ham. Oh, Fidel's former gofer confirms, too, the heftier ''secrets'' that Cuba experts have talked about for years: how the brothers assemble dossiers on foreign businessmen who want to invest in Cuba, for instance. It's Fernández's knowledge about Fidel Castro's dirty laundry, though -- literally and figuratively -- that has made him a cause célbre in South Florida. No detail about the Castro brothers seems too small for sharing...