If Faraday sent Desmond to meet him in 1996 he should remember it. However the non-linear function of time in an equation such as this can be very difficult to predict. It is all basically theoretical. The memory problems that arise would just be one aspect of disturbances in linear time flow. When two distinct realities converge it should be somewhat like an eddy in the water, or two oscillating waves. One function may cancel the other out, or they may exist side-by-side in perpetuity. This could lead to an unstable version of reality in which certain possibilities come into and go out of existence.
When Faraday is watching the news footage of the crash he is greatly disturbed, likely because he knows he is about to collide with something he forgot about long ago. Or else he does remember meeting Des and the footage of the plane wreck is the solid proof he has been looking for that he isn't crazy and the island actually does exist, and he is about to go there.

NOTE: I am not a physicist or scientist by any means, just a casual reader of books on quantum physics.

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