I believe that Jacky Daly occasionally plays DG although his system of choice is C#D. Both systems would allow more harmonic playing than the prevalent (in Ireland) BC systen. quote
    imcorrect, it depends how the bc is played and what system of basses the bc has, there are two different arrangement of basses if for example the player plays in c major and b major and the basses have not been retuned, there is plenty of scope for harmony, the older models of Hohner double ray had basses that enabled you to play in b major and c major