I've brought up similar topics before, but I have a different, related question: what does Zanarkand look like once Tidus leaves? Is Dream Zanarkand a persistent world? Or is it a kind of Groundhog Day?
The whole Jecht getting to Spira by falling through some temporal vortex out in the ocean while training is a bit bollocks imo but it's a satisfactory enough excuse for how he left, but the idea that Auron could just cruise through riding on Sin's back is a little bit bonkers.