The moment Ryan Wedding’s life pivoted from one kind of white powder to another can be traced to the chilly slopes of Salt Lake City, on Feb. 14, 2002. The 20-year-old Canadian snowboarder was already being discussed as a superstar in the making, and was now preparing for his first Olympic qualifying run in the parallel giant slalom.He had been groomed from a young age for this chance, after growing up near Thunder Bay in a family that ran the Mount Baldy ski club, with multiple competitive skiers in its ranks. Mr. Wedding had joined Team Canada at the age of 15 and raced around the...