Filed under: USA, SnowboardPARK CITY, Utah (AP) -- Shaun White was so angry following a rare halfpipe loss two weeks ago, he decided to ditch a planned vacation for a little extra practice instead.Good call.The snowboarding star put together a near-perfect run Friday -- unveiling his latest trick in the process -- to dominate the U.S. Snowboarding Grand Prix and send a message that he's more than ready to defend his Olympic gold medal at Vancouver.