I've used this exercise in every workshop I've taught and it has turned out to be one of the favorites. I think it helps the student to face the fear of using paint and especially enough paint. You've probably heard the phrase "paint like a millionaire". This exercise shows loading the brush and application in a way that creates a surface quality that looks like frosting. With a preset number of allowed strokes it makes you really plan and think about how much paint to mix for the area you want to cover. It helps me avoid the "overworked" look of the paint.