Late reply here. Iternabe, when I first submitted my post I thought of you and the Feuchtwanger method. It's not my teacher's approach, but I should look into it more...
ranjit But in my experience, if you take this literally, you will have to work fairly hard with the forearm muscles to keep them up.
Yes. My body type isn't helping (curse my long arms!). I don't think my body and limbs would ever have picturesque form to impress a teacher. If I rigidly adhered to "90 degree elbows" AND "fingers holding a ball" rules, I don't think I could do it without introducing tension somewhere.