Agreed. It's interesting to look a little more into his numbers though. Here's what he did:
Stretch #1 (Apr 9 to Jul 18)
18 g, 102.0 ip, 101 h, 48 er, 38 bb, 99 k, 4.24 era, 1.36 whip, 8.7 k/9
Stretch #2 (Jul 23 to Sep 7)
7 g, 32.2 ip, 45 h, 30 er, 20 bb, 37 k, 8.27 era, 1.99 whip, 10.2 k/9
Stretch #3 (Sep 13 to Sep 29)
4 g, 26.1 ip, 16 h, 9 er, 13 bb, 31 k, 3.08 era, 1.10 whip, 10.6 k/9
So the first big stretch he was solid. Not great, not bad, but definitely better than the average SP in the AL. That second stretch was horrible. But that third stretch he was outstanding.
You could really look at him in three ways:
View #1 (the whole enchilada). This view holds that he's an average or slightly below average SP in the AL. His full season stats suggest this is the case, as he puts up a below-average ERA+ figure (89).
View #2 (they figured him out). This view holds that he was ok those first 18 games, but the last 11 they had him figured out and he struggled to the tune of a 5.95 era and 1.59 whip.
View #3 (that middle stretch was a dip in an otherwise very encouraging first full year in the majors). This view holds that, for a rookie, he shows a lot of promise. If you take his first and third stretches and combine them, here's what those 22 games look like:
128.1 ip, 117 h, 57 er, 51 bb, 130 k, 3.99 era, 1.31 whip, 9.2 k/9
And thus that bad second stretch of 7 games is seen as a predictable low that most rookies experience, but that he bounced back nicely at the end of the year.
I happen to subscribe to view #3. He has terrific stuff (very good curve plus a 95 mph fastball), and he strikes out a lot of batters (excellent k/9 rate). If he is controlling his pitches, he's downright nasty. Remember, he was just a 24-year old rookie this past year. There's a TON of room for improvement, but we've already seen very encouraging signs from him, and there's lots of reasons to be optimistic about his future as a starting pitcher in the majors.