One aspect of Frank Zappa's recordings that I've always found interesting and engaging is his habit of including "soundbites" and short conversations of the band talking about him or other subjects which were important to them at the time. Listening to his early recordings which included these snippets I get a sense of someone who was not only offering his music but also a kind of "folk recording" of events. I was unaware of the shanty connection, though. I may well have a VHS tape of the Zappa/Chieftains documentary festering in the garden shed somewhere. It was filmed shortly before his death.