Before making 2 starts: 19.1 IP, 19 H, 7 ER, 1 HR, 6 BB, 14 K
After: 2.2 IP, 4 H, 7 ER, 1 HR, 6 BB, 1 K
Now, correlation isn't causation, and I can't tell you about how his arm feels, etc., but there is a pretty clear effectiveness divide since his two spot starts. I took a cursory look at his pitch-FX data, but there's just not enough of a sample size during his struggles to see any pattern in the noise. Clearly, he should not be used in high-leverage situations until he re-discovers his old form, and if he continues the way he has the past two weeks, a trip to the DL or back to Sacramento may be upcoming.
The A's bullpen as a whole has gone through a recent rough patch, and getting Ross back to his original form as a valuable long-man/middle innings guy will go a long way in solving the problem.