Up too early so I'm trying to swipe this carefully.
If you visit the future, would it still be the same future when it came around chronologically? I mean, is the future a series of results based on a fixed set of decisions. Or is it a series of results based on a bunch of random 0 1 variables so that every look ahead is a toss of the dice. You may travel to the future and see something horrible and inescapable. Come back to the present and warn everybody. Then said event doesn't occur because, ie, a natural disaster, never happed due to some random variable setting off a future different to the one you witnessed. So in the end every jump to a future point, maybe 1 day, maybe 1 millennia, the same point, always yields a different series of results.
tldr :-/ Would you have to peek into a set chosen point in the future multiple times, then looking for overlapping trends based on conflicting data from sheer random variables, just to actually know high probability events in the future (ie a war) vs. low probably (ie an asteroid)?
Need more sleep :-(