"I wanted to explore deep, thoughtful theatre," deadpans a giddily vitriolic narrator, played here in a last minute swap-out by Mitchell Jarvis, during the eleventh hour of "Rock of Ages". Although referring to any aspect of this rollicking, trenchantly self-aware jukebox ride in classical terms may either be mawkishly generous or downright offensive to its recalcitrant intent. After all, in a production adorned with sequined motor jackets, zippy pop hits and fried and dyed locks, no one wants to bogart that joint.