Pity poor Aaron Fincke. Having your dad write a book, Amp'd, about your aggrometal band may be the least rock & roll career move ever. Thankfully, his pop, a 54-year-old English prof, doesn't fawn over his son, now the guitarist for Breaking Benjamin. Yes, the elder, asthmatic Gary Fincke dutifully drives hundreds of miles for concerts in tiny smoke-filled clubs, obsessively checks how many radio stations spin the group's single, and scans message-board posts from female fans who want to sleep with Aaron. But even while watching like ''a spy from the country of fathers,'' the starstruck dad curiously never shares his inner feelings about shuffling bandmates, his son's out-of-wedlock baby, and other events along the ascent to rock quasi-stardom. Yet the stage-side chronicles about intra-band relationships and the transformative power of skull-crushing music are insightful enough to make a son proud.