I'm comparing it with chess. Chess is pretty complex, complex enough that only a small subset of humans can play it at a very high level. Introducing computers to chess first led to a statistical and brute force approach. But once that had paid off and the results were in people spent a lot of time analyzing those results and this led to an entirely new class of engine that was far more efficient than what had gone before and which performed even better than the 'big iron'.

I would not be surprised at all if we will find that AI will go the same route. The fact that we don't know how it works is where the opportunity for improvement lies.