Before bringing the series home, Mark gets honest about what could stop this. In episode eight of The Long Course: four real barriers between the sport we have and the one we want — that change is hard even when we agree with it, that a calm pool hides a drifting sport, that good coaches clam up on things they're unsure of, and that nobody actually owns the health of the sport. None of them are villains. All of them are really the same thing: heads down. And not one is fatal — unless we let it be. Keep your heads up.