In a new TDN series, we curry lessons and wise counsel from veteran Californian figures who, like gold nuggets panned from the Tuolomne River in the High Sierras, have unearthed career riches on arguably the toughest circuit in the States. We begin this series with John Shirreffs. Born at Fort Leavenworth, Kansas, Shirreffs was raised around horses on his family farm, and was deployed to Vietnam with the Marine Corps before embarking on a career in racing, using a 10-year stint at the Loma Rica Horse Ranch in Northern California...