People forget that Silver's approach is basically weighting polls to figure out what the election will be, and he's the best "poll weigher" out there. But if the polls are systematically wrong, being the best at it is an unimpressive subtlety to the layperson.

To the extent 2018 brings increasingly contentious elections, we will likely see polling to remain inaccurate due to voter unwillingness to state unpopular opinions. In that case, multi-input "big data" approaches may prevail.

(Of course, it's also possible that 2016 is a "top" in terms of divisive rhetoric...only time can tell.)