Personally, I think that there may have been a hundred heroes like Chrono throughout all of history: some Dragons, some Reptites, some Men and princes of Zeal, some Mystics, and from races yet to come. The Chrono world, perhaps, may have been changed a hundred times, yet who would remember it? They only know things as the end result. Perhaps a thousand perils and ten thousand ruins lay in the future, and each time it was nearly averted. Gaspar, lying outside of time, would know this, and perhaps this is what he speaks of. To be honest, I seriously doubt that Schala teleported herself away from teh Ocean Palace. After all, Chrono Cross specifically states that, as the Palace crumbled about her, she fell into the Tesseract. That leaves no room to actually leave the Palace.