His plate discipline remained, though, which is huge for him.
I agree with Jacko that trying to predict his performance is like trying to find a needle in a haystack with your mouth, but my post translates to this:
If he's healthy, and regains his confidence, he'll be awesome and post a 900+ OPS, if not, he'll suck, and put up a below .800 OPS and fall off the prospect map. It's really that simple, there's no middle ground with a kid as talented as Anderson, he'll either flame out or start thriving again.