When Tidus first visits the Farplane, Rikku tells him that the "dead" he will see there are an illusion created from people's memories. Could this be true? Just because we know certain characters are "unsent" doesn't mean it isn't illusory. After all, (SPOILER)Tidus mother is there, and she is supposed to be a dream. Also none of the "dead" seem able to reply to the living, which is what you might expect if they were just illusions. (SPOILER)And Auron says that he doesn't "belong" there?