"The real question on Deja Vu is what one can do to trigger awareness of what happens next, before it happens. Precognition, ya dig?"
Hmmm, not sure if I'm right, but if you'd know in advance what would happen it wouldn't be Déjà Vu. Then it would be precognition as you point out. I mean isn't that the whole point of Déjà Vu? Only AFTER you've seen something you get the feeling that you've already seen it before.
As for precognition, you'd have to learn how to tap into the superconscious (aka. the collective conscious) mind.
John
j/k