Alan Jackson's a traditionalist in the richest sense, mastering just about every style and sound that has helped make country music the genre it is. On "Appalachian Mountain Girl," Jackson goes full bluegrass, pining for an old one-night stand while banjo and mandolin race in the background. "Seguro Que Hell Yes," meanwhile, offers a cheeky nod to the Tejano music that sprouted from the intermingling of cultures along the Texas border.