An instructor named Dave Marks has several video lessons on YouTube. Overall, he is quite amiable and seems to be knowledgeable as well. In this video, he states that you can correct a bad habit in your plucking hand by curling your non-used fingers in while playing. Take a look at the video to see what I mean. Do you think he is correct about this? I can understand about not having the hand tense, with the pinky pointing up to the sky and all that, but is consciously curling the fingers in important?