Yes it was. I remember way back when(Professor Peabody please help me remember) we used to do portrait drawings on canvas and then paint them in oils that we would draw a light in color evenly spaced grid on the canvas so that we could do the proportions correctly as well as capture details. I did not see this with this woman’s drawings.
I never got to oils, we used charcoal, pastels, quash, tempura, pencil, I can’t remember what else.
She just seemed to know what to do.