The relatively frustrating minigame is oddly addicting, even when I can see the computer cheating right in front of me.
Firstly, occasionally the opposing teams will drop one of their experienced old fogies in exchange for a new lvl 1 player that you'd find in one of the towns. This seems ridiculous at first, since they have pathetic stats and can't play for crap in comparison to the hardboiled players that populate the circuit. However, after you play them in their debut game, they'll suddenly jump from lvl 1 to lvl 35, the average player level right now. Of course, this simply isn't possible the other way around, where you'd have to some SERIOUS grinding in order to even get a 10 level jump.
The computer never learns or earns abilities, players on their team are simply given abilities at random. This doesn't seem like that big of a deal, since hey, the computer doesn't have a chance to grind for them like I do. It's a bit egregious though when almost every single opposing player I run into has abilities that are you simply CAN'T get any other way other than winning them in tournaments, which they don't because I'm winning them all. This is culminated in a running personal inside-joke where the blitzball players are giving the judges 'personal time' in order to get new techniques from them.
Also, probably just paranoid, but it damn, does the RNG hate my guts during the randomized calculations in-game.
Though, I'm still undefeated, even though I'm still only using the original Besaid Auroch members (Tidus, Datto, Letty, Jessu, Botta, and Keepa), so I guess the computer's got to do all it can.
While I like Blitzball, I think that they wasted a whole lot of potential, and could have made the game SO MUCH better than they made it.