Several months ago I attended a house concert featuring the superb Irish fiddler Gerry O'Conner . He was accompanied by a guitarist who played only in DADGAD tuning. I was particularly intrigued because he played some chords that you rarely hear in Irish or Celtic music. But when I talked to him after the show he confessed that he doesn't always know exactly what chord he is playing because he often lets the highest strings drone. Note that the highest strings are A and D. In other words, he was playing the same drones that we do on a dulcimer tuned to D! And according to Tony McManus , the DADGAD tuning originated as a slight variation of an open D tuning, so it makes perfect sense that Robin would have found the pairing of the two instruments to work so well.
P.S. I get dizzy just looking at that picture of Robin atop the rock on Lundy Island.
Dusty T., Northern California
As a musician, you have to keep one foot back in the past and one foot forward into the future.
-- Dizzy Gillespie