Full Swing · Mental Model

Pivot the fingers to the back of the palm in backswing

Moving into the backswing, the coach says to stay square and keep the same 'giving blood' relationship without changing the arm position, and simply pivot the fingers to the back of the palm rather than lifting the elbow out or turning the palm down. His core model is that how the fingers pivot relative to the palm is how the club head pivots relative to the handle.