Chris Jaffe at THT recently took a look at various facts around starting rotations.
So guess who was the worst rotation of all-time?
On the Royals in 2005, Jose Lima allowed 219 hits (including 31 homers) in 168.2 innings while walking 61 batters and whiffing only 80. As a reward for this horrible pitching, manager Buddy Bell decided to leave him in the rotation all year. Yeah, the Royals didn't have many quality pitchers that year, but Bell benched guys doing worse. In fact, Lima tied a record that year for lowest ERA+ (63) for any pitcher in MLB history with more than 30 starts.