Anecdotal observation from college: Lots of people got hammered on a weekend, at least sometimes, but the people who couldn't draw a line and keep it from destroying their grades were mostly the ones whose parents kept them rigidly controlled at home. It seemed like those folks had no practice in drawing their own lines because their parents always drew the lines for them, so when they were on their own they went nuts. The preacher's daughter is a cliche with a lot of truth.