When I left teaching History and English and started spraying the full season, I worked as an apprentice plumber the first winter. My boss, Mike Labor, was a great teacher. He used memorable illustrations to prevent common errors like installing sweeps backward. You don't forget, "farts up, turds down."
Why didn't I think of this earlier? Students tend to forget, or mix up the wine glass method to remember drainage. And they often avoid wind rather than learn its tremendous lifting energy over rising terrain. Here we have a way to remember both. Farts up: why not use 2,000 fpm free lift if offered? Pitch up in updrafts or fly ridge lift. Turds down: why not takeoff down drainage and use drainage systems (they're everywhere) to egress limited engine energy situations?