I would say the U18 champs aren't so much about winning but showing off the best of the draft talent available against higher quality opposition than most get to play against. So while every kid out there is a competitive beast, recruiters want to see what they can do.
That's why you see players in different roles each game. Henry played as a lead up full forward against Metro, a half forward against SA, a forward pocket against the Allies and an attacking wingman against Country. Robertson would spend half a game leading the midfield, a quarter in a back pocket taking kick outs and a quarter up forward showing off his marking.
WA were lucky in that they didn't stretch their players too far from their natural game and that all their players are versatile, mid range types like Rivers and Ruscoe. Other sides weren't as versatile (although most would argue the Country side is a better and more versatile team than WA but were jumped by a fresh WA after Country had played a tough game just 5 days earlier) so when players were moved out of position, they didn't have as much cover and their stars weren't able to carry them.
To me Biz, that is a Morganish way of saying Summa & co picked a team to win the Champs, and played them where they needed to depending on the team they were up against.