@vincentprendick, your brutal honesty is hysterical -- "any angle" indeed! I always really hate planning them but then actually going through with the drawing, issues resolve themselves. Not all of them, of course! But upon approaching and following through with a difficult angle, you always get something from the exercise. "Oh... the chin's shaped like this from the bottom!" "So that's how the arm bends, aa." "You can't even see a nose from this position, perfect!
It's a fun little math puzzle everytime, hah^^