It's a possibility, I won't argue with that. The Zanarkand that Tidus comes from only exists because of the fayth's dreams? Are they re-dreaming a new version of the destruction of Zanarkand to bring Tidus to Spira? that seems a little excessive. Jecht got there because of a storm right? And since (SPOILER) Jecht is the new sin, he went back in time to get his son to help and defeat him if I remember correctly... that's why Auron is there. It's not very clear. There are a few holes in the story I think.

Auron could of gotten there becaus (SPOILER) he is an undead and he managed to travel with Sin after he brought Yuna back to Besaid... I guess that would be the most logical thing. So are they even travelling in time or just dream walking the fayths?