Well he isn't lying about it being one of the ways to time travel, it's also one of the key methods to walking through walls and normal teleportation and it's one of the ways to change the past but it's usually more in unseen ways. But it depends what your skill level is. Theres a race here responsible for the interactions of realities, some people call them watchers but not like the watchers on sci fi, they are more like guardians of truth. When you're in a room with ten people with drastically different realities they alter things so that there is less dissonance between them which does effect more than one being.
And there are humans that do similar work in the astrals all the time, they use time travel as one of their weapons especially in rescue missions. But i've never heard of stopping nukes, it's usually the normal et's that do that. But I suppose anything is possible.
