Oh. No. Wait. It matters more than anything else. Ask any other mandolin or guitar player. He'll tell you the right way. This is a useful strategy for any piece of technique.
I went to a flat-picking workshop with Dan Crary, a Winfield, national flat-pick-guitar champ. Dan's a great player, a great teacher, and has some very nice books.
He spent about 15' explaining why the only way to be a good flat-picker use your little finger to anchor your right hand to the top of the guitar, so that you know exactly where it is. He's studied the problem, and now knows that all pick motion is to be done with the thumb and forefinger that hold the pick. There is no other way, he says, to get the speed and accuracy you're striving for.
When he paused, I asked, "What about Doc Watson?"
Doc Watson's forearm is as stiff as a two-by-four from the elbow down. The only thing that ever touches his guitar is his flatpick. He can't very well be looking to see where his pick is, either, since he's blind.
"That's a difficult technique," Dan explained.
Spend a few minutes listening to Bill Staines or Libba Cotton, who play guitar upside-down and backwards. They make a living at it and play better than you do. I find watching them surprisingly confusing.
The right way to hold the pick is the way that works for you -- whatever feels natural.
This my answer to most questions about technique.
Django Reinhart was in a fire as a child. He had first- and second-degree burns on more than half his body. His left ring and pinky fingers were paralyzed; he's finding every note of every solo you hear him play with his index and middle fingers. It ain't called Hot Jazz for nothin'.
Me, I'm boringly conventional. I make a little loop with the thumb and forefinger of my right hand, slip the pick in between the two, and play. I'm not entirely sure what I do with the rest of my fingers. There's probably a better way.
Theorizing's for theoreticians -- people who write books. We're here to play tunes.
