With a handful of gel packets stapled to his bib, American Noah Hoffman would have blended in better at the American Birkebeiner than into Sunday’s 50 k freestyle at the 2011 World Ski Championships. But make no mistake: the way he was skiing was still world-class. Hoffman made it more than 30 kilometers rubbing shoulders with the World Cup podium’s usual suspects—Petter Northug (NOR), Lukas Bauer (CZE), and Maxim Vylegzhanin (RUS)—before finally succumbing to the...