Thanks, Mike. That's how I understood it. Here's what the manual says:

"Clutch rating factors in "results" like ERA, Save percentage and Inherited runners scored.
Therefore a pitcher with high grade and low clutch may have great hits allowed, hr allowed and walks allowed stats but pitches better with no one on base.
Conversely, a pitcher with high clutch and low grade does better with runners on base."

One point: Is save percentage a good indicator of this? If the idea is to give some credit to pitchers that do well in the 9th, as opposed to the 7th and 8th, shouldn't absolute number of saves (or maybe Saves-BSx2) be used? To expand upon my earlier example, LaTroy Hawkins had 0 saves and 3 blown saves, and a clutch rating of 7.6, JC Romero had 1 save, 4 blown saves and a clutch rating of 8.1, John Smoltz had 55 saves, 4 blown saves and a clutch rating of 4.6. It's pretty clear that Smoltz has the goods on the other two in closing out the game. (Maybe Smoltz is a fluke, but I have been thinking about this for awhile, so went looking for an example. These three guys were the FIRST ones that I looked at--I just sorted the 2002 stats by innings and started looking for relievers with close to the same IP.)

One question: How much does the clutch rating affect the pitcher's stats? Presumably, a pitcher with a clutch rating of 5.0 pitches exactly as well with men on as with the bases empty. How much worse does someone with a 3 rating pitch with men on, and how much better does someone with a 7 rating pitch with men on?