KEITH STEGALL Artist, songwriter, producer—he’s seen success from all sides By Michael Gallant When it comes to country music, few producers have made as profound a mark as Nashville’s Keith Stegall. The multitalented studio master has produced more than 20 platinum albums and sold more than 70 million records. His résumé includes 50 No. 1 hits, four Country Music Association Awards, 10 Academy of Country Music Awards—and the list goes...