At one point in his memoir of the Bristol Troubadour my brother mentions "Alex(?) Murphy and Shaggis". Actually it was Noel Murphy and Shaggis, and Shaggis was a teenage banjo player who later got more famous as Elton John's guitarist under his real name of Davey Johnstone. There's a pic of them at the Troubadour in 1968 here.
I never met these people, but I was at a folk club in Somerset a couple of weeks ago (The Old Down Acoustic Club) and Shaggis' ex-wife Diana Johnstone
Al Stewart certainly seems like someone it would be interesting to share a crate of wine with.