I'm inspired to ask by DK's phrasing, that Duke once again "hit a wall": was effective for several innings, and then became the batting practice thrower that he was a few years back.
Now, I suspect that the gut response will be that the guy's stuff isn't very good, and that he has a weak defense behind him and not enough Ks, and so big innings are inevitable. But that's not what DK's been describing the last couple starts. And that's not what we see when Duke is off his game: we've seen plenty of starts in which he looks hittable from the first batter on, and it's a struggle for him to give up only 4 in 5 innings. So I feel as if these starts are a different phenomenon (I should note here that I haven't seen either on TV, and last night I had guests and missed basically the whole thing, so this is based on limited impressions).
What I can't figure out is why a guy with Duke's profile would "hit a wall." His arm can't possibly be wearing out from heaving 89 MPH FBs, and he's been in the league more than long enough to be suffering from lost focus or mental fatigue. Or so I'd think. So what's going on?