Well, yeah. Saiyuki is not Xi You Ji. It was never meant to be. It was very clearly never meant to be, and I have canon evidence.
Everybody remembers the fake-Sanzo-ikkou, right? The Hakkai who was enormous with a piggy nose, the wimpy Sanzo, the Gojyo who didn't have much in the way of personalilty, and the Goku who had a certain cunning and acted as a kind of a leader?
These were much closer to the original characters, and that's a small part of my point. What I mean is:
* at the beginning of that first episode with the fake-ikkou, the village elder is telling the story of the Sanzo who passed through the village a long time ago (note please that it's the village elder who's saying this, and that he doesn't place the event during his life) and saved it from youkai. Was that our Sanzo? Absolutely not. Sanzo's not old enough, as he tells Goku.
Was it Sanzang? ...Probably also not. The sutra that was used in fighting the youkai was the Maten Sutra. Even if Sanzang had had that sutra at the time the was passing throught the village (and been able to distinguish it from all the others as a weapon), he probably wouldn't have used it. He had his own, spoken sutras to defend himself with--sutras he was accustomed to--as well as his disciples. Also, the Maten was a holy relic to him. Sanzo wouldn't hesitate before using a holy of holies as a relic, of course, but Sanzang was considerably less irreverent.
* Sanzo is not the first holder of the title. There was Koumyou before him, and some thirty-odd before him. And that's just the holder of Koumyou's sutras, never mind the three others.
* But he is a Sanzo. Sanzang was never a Sanzo as Minekura uses the title. A Sanzo is someone who protects the Holy Scriptures. Sanzang wasn't protecting them--he was aquiring them. And when he was finished, he became a Buddha. Not a Boddhisatva. As soon as he reached the West, he was enlightened and out of the game. Or maybe he decided to stay after the curtain came down; that would make more sense in Saiyuki terms, since they're both supposed to be the Golden Cicada.
(And also since Sanzo is as cranky as we could expect someone who's denied satori to be. So, was Homura really after his Original Yang? Was that what all that was about? ^.^ )
What all this means is that Saiyuki is Xi You Ji's future, not its self. But that was obvious the moment Sanzo lit up and they climbed into an automobile, even disregarding the differences between Sanzo and Sanzang's missions.
This does present us with a problem, of course: names. Or, why do they have the ones they have? Genjo Sanzo as a name is easily dispensed with; there have probably been a dozen Genjo Sanzos since Sanzang, and Koumyou would have wanted to make him look as legitimate as possible, given his age.
Gojyo and Gonou also present no difficulties. These are just good, if probably high-flown Buddhist names. They may even have been given them as a joke, especially Gonou, since the surnames match. And as for Hakkai... either Sanzo or the gods gave him that name, and my money's on a certain smirking Boddhistatva, who may have considered it fair warning (I think I'm going to have to write that).
Goku is the real problem. He has not only Monkey's name and title but his origin story. There are a couple of possible explanations for this, among them that becoming a Buddha didn't take for the itan and Seitan Teisei is now in a state of permanent betrayal over being abandoned by Sanzang, or that Monkey got bored with Nirvana (not improbable, given Monkey) and decided to get born from his mountain again at the next turn of the Wheel. Heaven would have been watching Fruit and Flower mountain very carefully, of course, and snatched him up before he could build up another power base of monkeys or learn any Taoist tricks.
These are a couple of possible explanations. I eagerly encourage people to come up with their own--call it a reconciliation challenge! How does Saiyuki square with Xi You Ji? If people are interested and want to give it a shot, I wouldn't mind putting up a page for that. Fiction, art, just telling how it could have happened...
Anyone who wants to participate, send your entry here.
Email: Nightfall@suntemple.org