>>as far as music goes, his work was pretty insignificant<<
I'd rate him at least as highly as Butch Vig, who has really only produced one band, and engineered on a couple of well known albums. Morrissey's ...You Are the Quarry basically kick started Moz's career from the doldrums, in large part thanks to Finn's production. And love/hate Blink 182, their sound was copied by hundreds of pop-punk bands, and guy's like Fall Out Boy owe a lot to their sound.