As has been well documented, Chuck throws mostly fastballs and some changeups, while his slider is no good. Most LOOGYs throw breaking balls, lots of them. Here are pitch breakdowns for some of the more successful LOOGYs of 2007. (Pitch breakdowns from Bill James Online. Other stats from Baseball Reference.)
Jamie Walker, Baltimore: Tied for AL lead in appearances with 81. 33 percent fastballs, 28 percent changeups, 38 percent sliders.
Scott Downs, Toronto: Tied for AL lead in appearances. 61 percent fastballs, 24 percent curveballs, 10 percent sliders.
Pedro Feliciano, Mets: 58 percent fastballs, 7 percent changeups, 29 percent sliders, 4 percent curves.
Jimmy Gobble, Royals: 57 percent fastballs, 33 percent sliders, 5 percent curveballs.
George Sherrill, Mariners: 73 games, only 45.7 innings. 66 percent fastballs, 24 percent sliders.
The exceptions are people like Joe Beimel, who throw almost nothing but fastballs. A fastball-change repertoire is ill-suited for a specialist role, because changeups thrown by lefthanders break towards lefthanded batters. Chuck, in fact, has very little of a split; last year, he allowed a higher BA to righthanders but allowed more power to lefties. Over his career, he has actually pitched worse against lefthanders.
He could be a long man or a traditional setup man, but frankly hardly any lefthanders do that anymore. They’re either LOOGYs or the occasional closer.