There's a reason why Dave Grohl is known, however naively, as "the nicest man in rock." A reason why millions have bought his Foo Fighters albums and DVDs, his concert and festival tickets. A reason why generations have bought into his story, his dream, his self-fulfilling prophecies. Dave may not have the savant glamour of Nirvana's Kurt Cobain, but whereas Kurt dwelled in darkness, Dave was a lover, not a loner, a bringer of light. Foo Fighters:...