Brad Lidge has been far from "lights out" this season. It seems batters are laying off his slider and Lidge is struggling. His K/9 is 9.6; he's never had a season below 10.3 and last year it was 11.9. His BB/9 is 5.5, which is a full BB higher than last year, which was his worst season going back to 2002. He is allowing 2.75 HR/9, which is well above his 0.84 career average, and foes have a .400 BABIP.
His pitch selection, at least cumulative, mirrors last year. He's throwing 44.8% fastballs (93.4 mph) compared to 43.4% (94.3 mph) in 2008. He's throwing 55.2% sliders (85.2 mph) compared to 56.2% (85.1 mph) last season.
Lidge's first-pitch strike percentage is a career low 49% this season. He is throwing 43.6% of all pitches in the strike zone, which is also a career low. Without tracking every AB, it would seem he is falling behind in the count and having to throw strikes. The batters are taking advantage of those offerings.
Hitters are swinging at 29.2% of Lidge's pitches outside of the strike zone, nearly identical to last year. But they are swinging at 64.1% in the strike zone, compared to 59.1% in 2008. Also, they are making contact at 86% in the strike zone, compared to 78% last season and 75% historically.
So armchair analysis would suggest Lidge is the victim of patient hitters/poor control and some bad luck.