The tragic deaths of Evgenia Shishkova and Vadim Naumov in a plane crash late last month in Washington have shone a spotlight on the role of Russian- or Soviet-born coaches in the world of competitive figure skating. Their influence has shaped a generation of American skaters, raising the question: Why have these coaches been so successful in the U.S.? Maxim Adams has the story. Video editor: Serge Sokolov, Anna Rice  
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