By current count, there are more than 300 wineries in and around Paso Robles, California. Some, like Austin Hope, can trace their roots back to the 1970s winemaking renaissance in Napa and Sonoma. But others, like McPrice “Mac” Myers and Susan A. Mahler, are shaking things up and taking their industry in exciting new directions. There’s also a dynamite new foodie destination in town, by way of Napa, called FINCA, home of the chipotle-butter-grilled oyster. Though he’s a relative newcomer to the scene, Myers’s wines—particularly his blends of Rhone varietals—are the exciting results of an ongoing work in progress. With a flair for the unpredictable and a willingness to take chances, this winery promises to be a multiseason phenomenon. What I found equally engaging was the story of Myers’s back-door entry into the high-stakes game of winemaking and the delight he takes in being the feisty working-class new kid on …