Pain in the Thumb Solution One: No Motion in the Thumb Independently of the Hand as a Whole.
January 26, 2018
Example: Right Hand Playing A Scale Upwards.
Pause in the scale on the note played just before passing under the thumb. While paused, don’t let the thumb make any anticipatory gesture of moving under another finger. Just relax and pause.
Raise the entire hand, vertically, until it is several inches above the keyboard. While doing this the thumb makes no movements independent of the hand as a whole.
Have the arm transport the entire hand rightwards, until the thumb, still just an undifferentiated part of the hand, is poised over the note that it is about to play.
Simply lower the hand back down onto the keyboard. Still without any particular motion in the thumb that is not simply the result of moving the entire hand at once.
Sound the next note by moving the mass of the combined arm and hand.
Get used to there being a silence in the scale between the end of the note before the thumb is used, and the note on which the thumb is used.
Gradually the silence between the notes will shrink towards zero, while the absence of independent motion of the thumb still remains.