My brother and I are in the same fantasy baseball league, and we occasionally send each other overly long comments about baseball and fantasy baseball. I think this recent e-mail might be of some interest to other people:

I think the As are onto something quite interesting in regards to pitching. It's of some use to our league but also for general interest.

Let's start from the beginning. At the start of the decade, the As had 4 elite young starters who were deemed irreplaceable: Mark Mulder, Barry Zito, Tim Hudson and Rich Harden. Since then, they have lost all of them, receiving prospects in exchange for 3 of them. Though the team is currently mediocre, they have maybe the deepest collection of young pitchers in the majors and should be a major force within the next year or two. One of the major reasons this happened was because of their deals of these pitchers.

After 2004, they traded Mulder for Daric Barton, Dan Haren and Kiki Calero. Mulder would have one more excellent year for the Cardinals at age 28 before becoming a nonentity. Barton was a very highly regarded prospect that now appears to be a decent 1B. Calero was a solid reliever for a few years. Dan Haren was a mid-level pitching prospect who became a top major league starter and eventually brought in a haul of his own, as will be discussed later.

The Hudson deal went significantly less well for the As. They received in return Dan Meyer, a highly regarded pitching prospect who never really made the majors, Juan Cruz, a former pitching prospect who has become a solid member of the Diamondbacks' bullpen, and Charles Thomas, a crappy minor league outfielder. Despite some drama, Tim Hudson has continued to be an excellent starter for the Braves.

Zito was allowed to leave as a free agent.

Beane flipped Dan Haren before the start of this year for a package of 6 prospects. The premier names were Carlos Gonzalez, a solid outfield prospect and Brett Anderson, a potential #1 starter. 1B prospect Chris Carter and OF prospect Aaron Cunningham were also considered helpful, and added on were minor pitching prospects Greg Smith and Dana Eveland. Gonzalez and Anderson have done as expected. Chris Carter is having an unusually good year in the minors. Aaron Cunningham remains a potential 3rd or 4th outfielder. Smith and Eveland, we will discuss later.

Finally and most recently, the As traded Rich Harden for reasonably good young pitcher Sean Gallagher, and a few decent hitting prospects.

In general, the As appear to have done terrifically from all of this. Of the 4 starters who were considered untouchable, two of them turned into disasters (Mulder and Zito), one is still excellent (Hudson) and Harden is Harden. In exchange, they recieved 4 years of Dan Haren, and Greg Smith, Dana Eveland and Sean Gallagher, Daric Barton, one outstanding pitching prospect, as well as a whole slew of good hitting prospects. Considering they effectively only gave up Hudson and Harden (and one terrific Mulder year), this is pretty damn good return. It's even better when one considers the salaries they avoided paying.

Some people have suspected that the As knew something about these players. They think that maybe they knew Mulder or Zito were due to decline, or that they were simply superlative scouts. I disagree. I think they are based off of a few shrewd insights on the part of the As.

Firstly: giving up the stars. Trading away elite 28 year old pitchers for prospects is not nearly as risky as it seems - it's actually a terrifically smart thing to do. Pitchers are always uncertain entities, but dealing away a 28 year old top pitcher is like giving up a gun in Russian Roulette that has already been fired 6 times. All of these starters (with the exception of Harden) had picture-perfect careers - no injuries, plenty of success from an early age - while with the As. The chances that that would continue until their mid-30s are rather low. A 50% failure rate for this type of pitchers isn't, I don't think, evidence of good As luck - it's evidence of shrewd logic.

The second major insight the As have had is that there is a major divide in how we judge minor league pitching prospects from major league pitchers. We rate prospects by potential and major leaguers by performance. This means that we rate a minor league who can be a #1 starter significantly higher than we do one with the potential to be a #3 starter without considering their minor league performance. On the face of it, this seems eminently reasonable. A potential #1 starter is a terrifically valuable thing, especially when one considers that even if he doesn't reach his potential, he's still be a solid #3 starter. A potential #3 starter would have to do very well simply to equal that. If he doesn't meet expectations (a common occurence for pitching prospects) then he is of even less value.

Except this doesn't quite mean what we think it means. An average major league starter is actually an immensely valuable thing especially if he is 23 or 24 and makes the league minimum. If you can get somebody like that, then you can make your team terrifically stronger. Consider the "add-ons" from the most recent Dan Haren deal: The surprising thing is that neither Dana Eveland nor Greg Smith have beat expectations. They're doing exactly what a moderately optimistic observer would have expected. Greg Smith was a very good minor league pitcher with a 3.27 ERA, and a 7.76 K/9 who was expected to be a a #4 starter. Though his first months on the As have been unusually strong (3.43 ERA, 6.04 K/9), there is every reason to think that he will settle down as an average starter with a 4.00 ERA or so. Dana Eveland was also projected to be a #4 starter, despite his 2.63 minor league ERA and his K/9 of 9. He has also done relatively well in the majors (3.49 ERA, 6.7 K/9). They were good minor league pitchers with limited potential who have become decent (and perhaps better than decent) major league pitchers. What is exciting about this deal isn't that they're having strong years, but even if they become simply average major league starters, the As will have gained alot. He'll have gotten for Dan Haren, in addition to two top prospects, two (low-salaried) Joe Blantons (major league ERA 4.25). And a Joe Blanton is an enormously valuable thing.

(I'm tempted to guess that this isn't the first time Beane has done this. Dan Haren himself might be an example of this, considered simply a good pitching prospect, and in whose first two years with the As had ERAs of 3.73 and 4.12. His last year and a half have been significantly better, but I don't think Haren was ever considered to be a dominant pitcher. Barry Zito was also considered an over-draft because he was not percieved to have the potential to be a #1 starter. We tend to think of potential #1 starters as people with the potential to be greats, while major league aces are usually just very good pitchers who get ERAs of say 3.30, rather than 3.90.) 

Now obviously there remain significant risks with this type of pitcher. Eveland and Smith turned out very well: it is equally likely that they (like Dan Meyer), would have slipped down and become not even #5 starters rather than the #3s that they are. As a rule, one would rather get top pitching prospects than marginal ones, like Beane did get, a la Brett Anderson. Yet even this isn't quite true. Brett Anderson is a terrific pitching prospect who is doing excellently, but the As got him before his 20 year old season in A+ ball. An awful lot of top pitching prospects collapse, either because of injury or other reasons, between 20 and 22 or 23. Not only are these marginal pitching prospects cheaper because of their lower potentials, but they can also be gotten older. A 23 year old pitching prospect who has already done well in AAA may be a significantly safer bet than even the best 20 year old prospect in A ball.

Beane and the As seem to be working from both ends. He's collected some of the top young pitching prospects in the game (Anderson, Trevor Cahill, Fautino de los Santos, and others) but he's mixing them up with a large quantity of decent pitchers who are still, because of the risky nature of major league pitchers, of tremendous value: Greg Smith, Dana Eveland.

Considering this is already way too long, I'll resist the temptation to discuss further connotations