As the crow flies, Klein, Texas, isn’t that far from the Louisiana border. But for Lyle Lovett, the town’s proud son whose travels have taken him to all manners of exotic locales, New Orleans is a strange, wonderful place that might cause him to act in ways not, well, Lyle. “Jazz Fest is legendary,” Lovett says by phone from his Klein home. As polite and gracious as any mother could ever want, Lovett audibly perks up at the prospect of his two Jazz Fest dates this year. “I personally shy away...