David Cook is the most overtly “rock” performer to ever win American Idol—butt-rock titan Chris Daughtry didn’t even make the finals—but while his victory in 2008 represented a bold development in the show’s history, fans of actual rock music might have trouble distinguishing him in Idol’s galaxy of easy-listening stars. He does play guitar, and guitar players have been known to rock. He also has a soul patch and flashes the devil horns a lot, which were once rockin’ signifiers. For last year’s David Cook, he worked with a collection of ’90s rock washouts, including Ed Roland of Collective Soul and dudes from The Nixons, Lifehouse, and Better Than Ezra. Inexplicably, rubbing shoulders with so much failure resulted in a hit album. Go figure.