Here’s what we know: Johan Santana is a Met. Over the last three seasons, he has probably been the best pitcher in baseball. Just look at the numbers: 100 starts, 684 1/3 innings pitched, 144 walks, 718 strikeouts, 2.99 ERA, 1.01 WHIP. Staggering. Mind-blowing, really. When you consider that he’s moving from a pitcher-neutral park in a hitter-friendly league to a pitcher-friendly park in a pitcher-friendly league…well it just makes Mets fans drool.

Here’s what we don’t know: Was the Santana trade a good one for the Mets organization? Wait a minute, didn’t I just get finished telling you how great Santana is? Yes I did, but there are many other factors that play into evaluating a trade like this one. First, we must consider the price. We gave up four prospects in order to get the trade done. Evaluating prospects is an inexact science, but none of the four we traded were considered blue-chippers. So far, so good. Next, we have to consider what we got. Wait, we got Johan Santana, right? Not exactly. We got Johan Santana for this year, and the rights to exclusively negotiate a contract extension for him.

Some people marvel that we got Santana for less than the Diamondbacks paid for Dan Haren, and less than the Mariners will likely pay for Erik Bedard. One difference is that Haren is under contract for three more years. Bedard is a little tougher to explain, as he will become a free agent after this season. Maybe the Mariners will overpay. Maybe the deal won’t go down at all. The point is, a team doesn’t just trade for a player, it trades for his contract. The Mets could’ve decided to wait a year, and then tried to land Santana via free agency. The downside was that Santana’s contract would’ve cost more, we might not have been able to sign him even if we’d made the best offer, and the Twins might’ve traded him to another big market club, taking away our chances to ever get Santana. The upside was, we could’ve potentially landed Santana and kept our four prospects. This is why I disagree with my colleague Matt Cerrone when he writes, “instead, we could have collectively hoped and prayed that one of Mike Pelfrey, Phil Humber, Kevin Mulvey or Deolis Geurra would turn in to Santana.” No, it wasn’t that black-and-white. We could have possibly had Santana, and still had all those guys. Just not in 2008.

So how do we analyze the trade? I don’t think we, as fans, are interested in whether the Santana trade will be a profitable one for the Mets organization in terms of dollars and cents. As fans, the value of our team should be measured in championships, and to a far lesser extent divisions titles, playoff appearances, and wins, probably in that order. A championship is the ultimate prize, though. Most fans I talk to would probably enjoy a championship ten times more than a mere playoff appearance. Just ask those of us who were along for the ride in 2006.

If Johan Santana appreciably increases our chances of winning the World Series, then I am all for the trade. The problem is, it’s very hard for one megastar to appreciably increase a team’s chances of winning the World Series. No matter how good a player is (and as I noted above, I think Santana is a masterful pitcher, the best in the game), there is still so much luck in baseball’s playoff system that no team can have more than, say, a 25 percent chance of winning the title going into the season. If we’re going to be optimistic, the Mets went from about a 10 percent chance to a 20 percent chance of winning the 2008 World Series with the Johan trade. (These are not scientific calculations, they’re just numbers I’m using to make a point—but I do believe those guesses are pretty reasonable.) But we don’t know the front office’s plan for 2009 and beyond. Pedro Martinez, Oliver Perez, El Duque, Carlos Delgado, and Moises Alou all become free agents after this season. With our prospects now depleted, it will be very hard to replace these guys from within. Do we really have enough money to replace all these guys with quality options via free agency? Are there even enough quality free agents out there to do it? Does the Santana trade double our chances of winning the World Series of 2008 at the expense of lowering our chances in 2009, 2010, 2011, 2012, and 2013? Do we drop back down to a 10 percent chance in all those years? And if so, should we have maybe held off a year and tried to pry Santana loose via free agency?

I don’t know these answers, and because I don’t know these answers, I objected to many of the trade offers I heard rumored for Santana. Specifically, I was against including Jose Reyes in any trade, I was against any four-prospect trade that included Fernando Martinez (who is supposedly the only blue-chip prospect we have), and I was against any trade that involved more than four prospects. Let’s give Omar Minaya some credit. He got the deal done for four second-tier prospects. Omar’s refusal to give up Martinez means that this trade clearly wasn’t a bad one for the Mets. But it wasn’t clearly a good one either.