You know, this is why the Timeline Temporal Displacement technology was deeply hidden and locked away in the Department of Mystery in the Ministry of Magic in Harry Potter - the wrongfully usage of this technology is very dangerous. With the "right" people, they can revert to the time before human civilization's creation, thus undoing us all. Or in the hands of uproght, good people, redirecting the development of humanity on its rightful path (but do we really need that?).

Thoughts?