Well, try this simple experiment. Tilt your head 90° and nose-breathe. Now grab your up-facing nostril and pull it wide open. You're probably taking in a lot

Well, try this simple experiment. Tilt your head 90° and nose-breathe. Now grab your up-facing nostril and pull it wide open. You're probably taking in a lot more air now, with zero resistance. That's what these tubes do.