I'm pretty sure I have more than a couple strokes, I tend to block some shape out then undo until i like it. You don't see the undo's that I do. I keep my brush larger until I like the general shapes and then i go smaller. If you spend 2 hours doing some small detail and then don't like it you are less likely to fix it. Where if you like the shape when its larger then it is just more polish until its done, and you can stop at anytime and still have something decent.