In the end, boys or girls, the real question isn't whether you have 32 kids who can play anywhere else, but rather whether you have a significant spine of 12-14 who can withstand significant minutes when the chips are down.
The Wando boys' mass-substitution pattern worked great against inferior opposition. (All the mommies and daddies were happy that Nos. 24-32 were getting significant varsity minutes.) But it didn't enhance match fitness for the core, and it effectively created a situation in which Mann scored the game-winner when Wando had a handful of key players off the pitch.
As to the original question -- the achilles heel -- MOST championship high school teams are, almost by definition, built around upperclassmen. When those kids inevitably graduate, the dynamic changes. Some schools/programs survive graduation losses better than others.
