Poor venomblade, we never got to answer your question. Actually, I think this is very good and actually accurate. Young Xehanort could very well be the only REAL Xehanort in the Realm of Sleep. He could be younger for the reason Sora and Riku are, but we don't know anything about that, so it's not really safe ground to theorize in. Also, just to trow my two cents in, (And just so you know, I did not steal this from Grass' theory, I came up with it over a month ago in the former worlds thread.) I think Xehanort is in the Realm of Sleep to find Land of Departure and awaken it so Castle Oblivion can change form, so he could retrieve Ventus due to Aqua being the only one to do it manually inside Castle Oblivion. This is because Land of Departure and Castle Oblivion are two sides of the same coin, one is awake/existing, while the other is asleep/gone. Right now, Castle Oblivion is in the former position with Aqua being the only one to change it inside, but in the Realm of Sleep, Xehanort still has a chance of his own. Anyways, great theory! I'm a very great supporter of it!
Thanks for the response and that may very be true about the LoD. When Aqua sealed the land away I just thought it ceased to exist, but it probably is "sleeping' as you said. Do you think Xehanort wants to find Ven out of malice? Or do you think he remembers a bit as Terra and wants to save his friend?