Somewhat oddly, Penny's ERA is lower than that of Alvarez despite allowing more hits and walks and striking out fewer batters per nine innings. The apparent reason: Penny allows home runs barely half as often. However, because he has allowed 32 doubles to Alvarez's 10, Penny still has a higher slugging percentage allowed than Alvarez, .386 to .357. Lima is at .462. (Side note: Penny's numbers may well improve with more games at Dodger Stadium and with more games backed by the superb Dodger defense.)

In any case, the difference between Penny and Alvarez is much less than the difference between Penny and Lima. So while the Dodger bullpen may be in better hands than people fear (especially if manager Jim Tracy makes liberal use of Alvarez as an additional set-up reliever, rather than as a situational reliver like Tom Martin, and if Yhency Brazoban fulfills his promise), the improvement to the Dodger starting rotation for the remainder of the regular season may not truly be what people are counting on.

However, Penny could make a considerable difference if Lima falters and Tracy puts Alvarez back in the rotation. It's actually a win-win situation - either Lima pitches well, or Alvarez can replace him. Penny is strong insurance against Lima's luck running out. The problem scenario is if Lima is ineffective but just barely good enough to stay in the rotation, while Alvarez withers from lack of use as a reliever.

Further, Penny could be a valuable asset both in the playoffs and in the event of another injury to a Dodger starting pitcher. If the Dodgers reach October, not only does No. 5 starter Lima automatically become a long reliever, but so might now-No. 4 starter Kazuhisa Ishii. With his propensity to be wild, Ishii is probably the Dodger pitcher least prepared for the postseason stage. The acquisition of Penny allows Jim Tracy the luxury of using a quick hook on Ishii, assuming he uses Ishii at all, because Alvarez or Lima can now be waiting in the wings, rather than expected to take their own turn in the playoff rotation.

Furthermore, should an injury strike the ever-vulnerable Odalis Perez, Penny leaves the Dodgers much readier to cope. In general, Penny really does revitalize the Dodger chances of having a championship starting rotation.

Paul DePodesta's mentor, Billy Beane, may believe that the playoffs are a crapshoot, but DePodesta made Friday's trade for Penny so that the Dodgers' odds in that crapshoot would be more favorable. People forget that in the mid-1990s, before Mike Piazza was traded, that people weren't satisfied for the Dodgers to simply make the playoffs - everyone wanted October wins. Now, it's been so long since the team has even played a playoff game that many have forgotten that the playoffs require something extra.

In questioning why DePodesta would make dramatic moves to a team that is already winning its division, some have forgotten that a division title is not the ultimate goal. If Jim Tracy takes full advantage of the depth provided him everywhere but catcher, including the bullpen (almost every major-league team would still trade their bullpen for the Dodgers'), the various reservations that people, including me, have over this weekend's trades may fade behind October glory.

And the thing is, although Tracy does not always get it right, he has proven to be a manager who learns from many of his mistakes. There really is reason for Dodger fans to be optimistic, no matter how lamented the departure of some Dodger heroes.

P.S. Thanks to those who reminded me in the comments of Sunday's posting that VORP is cumulative and playing-time sensitive.