We live in a multiverse; there is not one reality, but many. There is not one you, but many each existing simultaneously in an boundless "smear" of parallel earths. Each parallel universe interacts with all the others like strings in a spider web, a complex tapestry of interactions.

That is why John Titor by telling us about future events prevented them from occuring, not only on our timeline, but possible even on his. This may have been the real intent in his time travel.

Using Steven Gibbs HDR I have attempted astral time travel on several occasions and the information is not 100% correct, in fact, much of it is often slightly off, and even wrong. Astral time travel is not a fool proof way to gain information. I have found that the further out you go the less releable the information.