chord changes can also be irrelevant, i have just been playing peggy and the soldier in double c using double thumbing[and a g drone, works perfectly getting away from chords, and using a drone gives a n unfinished sound specially where the c chord might be used just using cgcd, creating a suspension, this is what Carthy is always on about. i also play it in standard tuning on guitar using c and g chords works fine but is different both are good