Great! Exactly. That angle of the back wrist (or in other words, right wrist for a right hander) helps keep the shaft in line with the front arm. This shaft in line with the front arm will have the grip end of the club leading the club face… and that is critical for a solid shot/putt. If there is hinging of the wrists on the backswing, it will more than likely make you “flip” or “throw the club head” through impact. It is almost impossible to hinge the wrists on the backswing and then create a shaft in line front arm through impact …. the club head wants to flip… Thanks Femgolf_10 for the great insight.