Penguin Egg, that may be your honest opinion, but there are ways to say things, and that wasn't put very well.

As to your question, what has he done? Davey Graham created the style of guitar that Bert Jansch and John Renbourn used; just ask them. Without him there wouldn't have been the version of Goodbye Porkpie Hat you enthuse over, because it owes its in technique and theoretical approach entirely to that first seen on 1959's 'The Guitar Player', an album that pretty much invents the idea of the guitar instrumental in a non American blues or classical setting, even if it does have a rather overenthusiatic drummer. Folk-blues guitar and jazz were mutually exclusive in this country before Graham, as were Folk-Blues guitar and trad.