ok,Ray. Roscoe Holcomb did that,
the percussive damping is reminiscent to some extent of hitting a 5 string on banjo and damping, and playing melody up[ when he played melody] pete seeger style, of course Nic did a lot more than play melody in open tuning. the tuning cgcgcd could be derivative of a banjo double c or alternatively banjo gdgcd known as sawmill