On the surface, past performance seems like a truly excellent way to predict future performance. We do it all the time in relationships: "Well, you lied to me 4 days ago and then again yesterday. So...yeah, not really trusting you a whole lot tomorrow." But enough about why I'm sleeping on the couch this weekend.

In baseball, the past can help to predict the future -- sometimes. Lying doesn't really decline with age, but bat speed and fastball velocity can. When the Angels signed two superstars, Josh Hamilton and Albert Pujols, the players apparently had unfortunately had the tags ripped off that read, "Oh by the way, I'm just now taking a plunge from 'superstar' to 'utterly average player' on my descent into complete mediocrity." While we're on the subject, what is the obsession with people removing mattress tags? Is it some uniquely horrible crime the scope of which everyone but me understands? Is there a "Mattress Tag Unauthorized Removal" bureau in city's police department?

Here's where Billy Beane has been, and continues to be, so disciplined: The A's simply will not pay for past performance. They will pay only for predicted future performance. Never has this been more evident than this off-season.

Oakland didn't re-sign Bartolo Colon for 2013 because they were wowed by his 2012 results. They clearly felt he had at least one more good year left in his tank, and they were right. However, despite a better season in 2013 the A's avoided the Colon sweepstakes. Perhaps his elevated price tag was a factor and likely his desire for a multi-year deal was influential. But maybe also Colon's August "running out of gas...er, I mean, injury to..um, yeah, that thing" scared Oakland, along with the increasing ticking time bomb that is Father Time -- Colon is entering his age 41 season and starting to push the boundaries of what his similar age peers have been able to accomplish.

In contrast, a pitcher possibly on the upswing is Scott Kazmir. Kazmir's overall stats in 2013 dwarfed Colon's, yet his second half numbers, his increased velocity, his K-rates, and his age all portend that 2014-15 could be very good years for Kazmir. And those are the years the A's are paying $22M to get.

Oakland got a lot of value from Grant Balfour, both as a set-up man and as a closer. And like Billy Koch, who parlayed some luck, some Houdini acts, some smoke and a few mirrors into a stellar season, Balfour is unlikely to live up to his next contract as well as he lived up to this one. In fact at age 36, he is not especially likely to be as effective a reliever going forward as the younger Jim Johnson -- not to mention Luke Gregerson, who might well be the best reliever of the three.

We have seen this before. Brandon McCarthy was terrific for the A's, yet Beane let him walk because he assessed that McCarthy might not be so effective in the future. Some of that probably related to McCarthy's injury history, some might even have revolved around coming back from the line drive/surgery. Arizona traded for what Trevor Cahill had done, and Oakland traded for what Jarrod Parker was going to do.

It's actually remarkable how many times Beane has been able to replace excellent contributors with younger, cheaper, and better replicas. Mulder to Haren and Cahill to Parker are two examples, Colon to Kazmir and Balfour to Johnson/Gregerson potentially two more.

Did the A's violate this principle with the Choice-Gentry deal? Not really. Gentry isn't younger or cheaper, but he is better now and he will almost certainly be better in 2014. So the A's made a "win now" move that may hurt them in the longer run if Choice thrives. Perhaps it's even another example of not paying for "past performance" -- Choice's pedigree -- if Oakland feels his ceiling is more limited than they thought at the time of the draft. Or maybe it's just that you have to give up talent to get talent, and you don't always fleece the other team; sometimes you help each other, just in different ways.

I do want to address the Johnson trade, and the notion that $10M is too much to pay to a closer. I see it differently. I think that if Johnson were being paid a salary thought to be more reasonable to pay a reliever -- say, $6M -- it would have sounded like a great trade if the A's had sent "Jemile Weeks and $4M to the Orioles..." Think of it this way: The A's paid $4M for the right to get a quality closer at a reasonable salary and only give up Jemile Weeks. That's a kick-ass trade in my book.

Back to my main point (no, not the one about mattress tags). Is the best use of your money, however much of it you may have to work with, to pay Robinson Cano $240M into his 40s because, well, look at how great he was in his 20s? The A's just don't do that, not with their own players and not with free agents, not with $240M and not with $2.4M. They pay for what they think they are going to get, and that's the future. And as long as your front office can make decent projections, it works.

The great thing about the past is that you can predict it perfectly. The thing about the future is that it's what's actually going to happen.