[neil]

I think what you are asking about "hinging" of the left wrist is actually the cocking and uncocking of the left wrist.THE RIGHT WRIST DOES NOT COCK..It only bends or remains bent.The left wristcock is a vertical motion-put your left arm out straight in front of you with your palm vertical,raise your thumb,point your thumb at your face...by cocking your wrist.It is Power accumulator#2.If you have the book see 4-0 and 6-B-2-0.If not I would buy a copy .