When you closely observe the right hand technique of some of the best mandolin players a pattern seems to emerge. It seems that most of them play with slightly to very opened hand and they drag the tips of their pinky and ring fingers on the pickguard or the top of the mandolin.
Sam Bush - Open hand, fingers touching the top of the mando, no pickguard (from his early days)
Bill Monroe - loosely closed fist, heal of palm and wrist touch strings behind bridge
Joe Carr - loosely closed fist, heal of palm and wrist touch strings behind bridge
Dawn Watson - open fingers touching the top of the pickguard
Simon Mayor - Open hand, fingers touching the top of the mando, no pickguard
Chris Thile - loosely closed fist, palm and wrist touch strings behind bridge
Hershel Sizemore - Open hand, fingers touching the top of the mando, no pickguard
Norman Blake - Open hand, fingers touching the top of the mando, no pickguard
Nancy Blake - Open hand, fingers touching the top of the mando, no pickguard
Ronnie McCoury - very open hand, fingers always touching top of mando, no pickguard
David Grisman - moderately open hand, curled under fingers touching the pickguard
Butch Baldassari - moderately open hand, fingertips touching pickguard, posts pinky to tremolo
Mike Compton - moderately open hand, fingertips touching pickguard
Ricky Skaggs - Open hand, fingers touching the top of the mando, no pickguard
Tim O'Brien - Open hand, fingers touching the top of the mando, no pickguard
Ronnie McCoury - Open hand, fingers touching the top of the mando, no pickguard
The Nashville Mandolin Ensemble - all but two touch down with finger tips on pickguard or top
Score:
Loosely closed fist - 5
Moderately open fist touching pickgaurd - 3
Open fingers touching down - 20