I told you something was possibly wrong with CC Sabathia. Based on his last start, I'd say he's fine.
I told you nothing was wrong with Jake Peavy. He hasn't yet shown that I'm right.
Let's look at another struggling star starting pitcher - Josh Beckett. His ERA is over 7. The good news is that his strikeout rate is 8.9, which is right about where I would have expected. His groundball rate is similar to last year too. I sometimes check whether there's been a sharp change (in either direction) in groundball rate to determine if something may be wrong with a pitcher. The bad news is that his control has been really awful, as he's walking over 4 batters per nine innings. That will be something to watch over his next two or three starts. At this point, I'd only discount his value ever so slightly in traditional leagues, but would generally favor other top starters over him in daily contest leagues until he shows good control for a couple of starts. Another slight concern in his statistics is that his strikeout rate may not be as good as it looks. Pitchers allowing lots of hits (whether through bad luck or not) face more batters. So the actual percentage of hitters that he's striking out is lower than it appears. In general, if you have easy access to the data, you're better off using strikeout percentage than strikeout per inning data.