One of my all time favourite books is "Learning To Draw" by Robert Kaupelis. He says blind (no looking at the paper) drawings should be a continuing part of your drawing activity, for the rest of your artistic life. And otherwise, when you do allow yourself to look at the line while drawing, your eyes should be on the subject 99% of the time. I think you could have a great art life doing nothing but reading his book, doing the exercises and and following his advice. I might have peeked at the lady, only once or twice!