Originally posted by Big D
I believe Maechen explained about the summoners volunteering to become Fayth after the war. That is, the Fayth in the temples around Spira; the Fayth Cluster on Mount Gagazet were probably all regular folk.

Seymour's mother is an apparent anomaly to this.

Not yet. I've seen that 'sad ending', I think - the one where (SPOILER)Yuna says goodbye to Tidus in the Farplane Glen, but I'm still working on that '100% completion'.
Fayth in the temples are summoners. I thought you meant all the fayth, including the fayth cluster. Ok. You think the kid who's Bahamut's fayth is a little young to be a summoner? Maybe he's a prodigy.

You don't need 100% for the good ending, you just need to complete a certain amount of criteria. You might think differently of what you said early about Tidus in the sea once you see the good ending.