Dream Zanarkand

[ReloadPsi]

What I don't get is how Sin is able to enter dream Zanarkand, bring Jecht out of dream Zanarkand into the real world, and subsequently I don't get how Jecht, theoretically an Aeon from a Fayth's imagination (well Aeons are the manifestation of a Fayth's thoughts, so...) is able to become a Fayth himself. Does that mean he could've dreamed a second (very small) dream Zanarkand and made an infinite amount of himself, had he not lost his self-awareness inside Sin of course?

And does that mean dream Zanarkand actually physically exists somewhere?

I've always blamed this on bad translation but I can't imagine it being written any better in the original Japanese script.