Iron Banner wasn't skill based; it was win based. Three good players on a team can make three shitty players shine. Four can carry the dead weight of two n00bs. Points were awarded for wins, not for skill. If it was skill based, then the winning team would get points and the top 2 or 3 players on the losing team would receive a lesser amount of points, but would at least get something for proving that you're an asset.