Ability to see the future: Loose plot thread?

[KageTokage]

I don't have a problem with Mikoto's future sight in itself. My problem was that it came from out of nowhere and how it was handled in the story. It wasn't written as good as it probably should have been.

That's the other beef I had with it.

The Echo has been firmly established to work by reading the "memory" aether of either souls or the environment, so being able to predict the future is decidedly not something that falls within the scope of what it's previously been shown to be capable of doing and they didn't even bother trying to handwave it by saying it's predicting the flows of aether or some such (Which is how Xenoblade did it).

Prediction of the future in general has been shown to be questionable at best, and the whole founding principle of Sharlayan astrology was turning it into a more...practical art by manipulating celestial aether in order to better work for/against the futures they believe to have foreseen.