Great track. Kickin' mandolin player. I think the drums might've irked Bill Monroe, but I know for a fact that Jimmy Martin approved of the sound of "Bluegrass Brushes."
Well the mandolin was a rythym section of sorts and Bill may not have liked the idea of replacement by drums.
Trad bluegrass had no drums but often filled with washboards or whatever was at hand or voice.
NewGrass blends em all