I posted my question on StackExchange so feel free to respond here or on StackExchange.
I’m looking for specific best practices around hand position and motion while using a thumbpick on an acoustic guitar. I haven’t found any specific resources on this. I have been impressed with Troy Grady’s Cracking the Code course on pick positioning and motion, and want a similar understanding for thumb picking. Here’s my current understanding:
Wrist should be rotated towards the guitar so that the palm is angled slightly upward.
Thumb should be straight and angled approximately -20 degrees, depending on the note (if 0 degrees is a horizontal line parallel to the neck of the guitar. Another way of phrasing this is that the angle between the thumb and the neck should be about 20 degrees.
Fingers should be angled away from the neck at a steeper angle than the thumb, around 75 degrees. Fingers should be far enough away from the thumb that the thumb does not hit the index finger on the follow through of the down stroke.
Here’s a picture of Mark Knopfler, and the corresponding video.
The thumb moves at an angle down and also away from the guitar. How much of the angle of attack is down and how much is away? The thumb remains straight.
The thumb pick has a downward slant, and the middle to trailing edge of the pick strikes the string.
The fingers have an angle of attack that’s upward and away from the guitar, but not angled as away as the thumb is. I think?
See Tommmy Emmanuel for an example.