See, this is the problem I'm seeing with FF fans. When playing a Final Fantasy game, rather than playing a final fantasy title as a game of its own, they often feel the need to compare FF games with one another when there really isn't really a need for such a thing. They keep the core aspect from each title, which happens to be the turn based mechanic. The summon mechanic is just them taking a new direction with the franchise. Though I also haven't played much to say a lot about it, I for one know that summons in the old FF games were just broken. In exchange for making the summons on average once per battle (or every few batt;es) in FFXIII, they made them ridiculously strong. They give a fair amount of advantage, but you didn't need to use summons to win, just good strategy.