Its simple. In set line up, substitutions are preset and they dont take into account exhaustion, etc. Thats why you have starting lineup play similar minutes. In blank, once a player becomes winded and ineffective, he gets subbed out and then comes back on when one of the players on court becomes less effective than player on the bench would be. This is simple, and I believe only way to maximize the resources available to a team. ANY game that is that close with set lineup used would be won fairly comfortably with blank. Just look at the game with Chile....... Team ratings look much better than during games before and after it. If you dont want to take my word for it or beanerz'.....just email any manager that had significant success in this game and you will hear exactly the same thing.
Why would you have any reason that we want anything but the best for Canadian U21 team and want to give advice that actually works?