I'm guessing you've never tried it. A team can play with 5 fairly easy. Look how many times teams hold off 2-minute penalties even on the World level. Sure it wears them down a bit, but if you have the occassional 6th man in there to break away and allow for a line change or breaks, it could prove to be advantageous. And nothing gets as frustrating as knocking on the door for a minute or two only to see them break out and make a long run on you. And even if they don't score it is a bit demoralizing to have to regroup and work it back up the pool. Now, I'm not saying I would want to play that game, but it could work.

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Just in case you weren't sure, it's official -- CMAS sucks.
Oh yeah, and now they're broke.