Great band. Apparently this song is about the first time he heard The Clash, the "ramshackle voice" he's referring to in the song is one Joe Strummer.
it is about the clash. the joe in the title is definitely joe strummer, referring to a quote by someone I can't remember comparing joe to one of his idols, woody guthrie. plus, joe used to go by the name woody for a while before he took the stummer moniker.