[crazygringo]

> Are we ever really going to understand why it produces the numbers it does?

I would expect so, because we can categorize things hierarchically.

A medium-sized library contains many billions of words, but even with just a Dewey decimal system and a card catalog you could find information relatively quickly.

There's no inherent difficulty in understanding what a billion terms do, if you're able to just drill down using some basic hierarchies. It's just about finding the right algorithms to identify and describe the best set of hierarchies. Which is difficult, but there's no reason to think it won't be solvable in the near term.