GREG KURSTIN Blazing his own trail from jazz scholar to pop hit-maker By Michael Gallant He’s produced a bevy of wildly successful artists including Kelly Clarkson, Pink, Ke$ha, Tegan and Sara, James Blunt, Dido and the Shins. But Greg Kurstin came to his hit-making career through an unconventional route—as a student of jazz piano. “I loved arranging songs and finding different voicings for chords,” says Kurstin, who studied at New York’s...