My teacher has got me using a thin wooden stick to measure against the live models. For the past few years, I've just been focusing on the separations of light and dark, so this new (old) technique has almost stopped me in my tracks. I've been spending most of my time trying to get accurate measurements and have everything fit into "boxes". It's frustrating, but I guess it's a matter of taking a few steps back to hopefully make a giant leap forward. I think I've got the basic gist of what I'm supposed to do with the stick and I'm hoping I can gradually incorporate it into my light/shadow method.