The best way, it seems, to make this shading technique work is if you have all the disparate lines, from each separate planes, all match each other. In other words, you should start a line at the top of the head, and be able to follow the line, down the forehead, all the way through the nose, lips and chin. The next line starts parallel, a few line thickness from the first line you drew and following the contours of the face, in then exact same way.
It seems, if you follow this idea perfectly, you'll get a drawing that looks as if you're copying a marble figure - something akin to the illustrations of the author's for the Wall Street Journal. It shouldn't be quite a surprise, but the whole technique becomes quite mechanical, if taken to its extremes. I'm pretty sure it can be created using a computer program. Perhaps.
Below is a Step Test for testing the exposure time for screen printing (here's a larger version, for detail):
I've been investing a little bit of money in my screen print setup, which sort of means, I've been buying a lot of wood and screws and making things to do stuff. I've gotten some fancy professional emulsion and I have no idea what the burn time is, so I've been experimenting. According to this print, around eight or nine minutes should do the trick.
The print is actually interesting to look at, but it's something that's been made thousands of times, by different people, for purely testing reasons. I remember, when I started screen printing, doing everything was sort of guess-work - I didn't quite know how everything worked, or what I needed and exposing screens was the most difficult part of everything, as the times seemed long and each burned screen seemed to be a gamble - would it work? A lot of the times, it didn't.
I did three such tests, with three separate burns, on three separate screens. Each one told me, the burn time is around nine minutes. And, that's it. Like tightening up the drawing style, it's becoming purely mechanical.
