He uses a lot of triangular shaped hatch-scribbles... but the way they are oriented (and weighted) on the "canvas" would imply that he is constantly rotating his hand/arm around the drawing, approaching from every angle. For watercolor / painting, this would be maddeningly labor intensive. I'd love to be wrong though...
Yeah, I can't see why someone would build an image like that. Even then, to achieve identical scribble each time, that would be something.