There's an age-old question when it comes to sports: Is it better to score a run or to prevent a run from scoring? The great philosophers of sports in general have carried this debate throughout history, what gives you the better chance of winning? Should you bolster your lineup and move the fences in or should you expand the yard and staff your squad with gloves and curveballs?
In a sense, there's really no difference. Scoring a run is supposedly the same as preventing the other team from scoring a run, as far as run differentials go. Having a positive and large run differential is typically the story of how a team wins pennants. I know this is a shock, that outscoring the other team consistently suggests that you will win a lot of games, but stay with me for a bit here.
Let's think about the nature of both of the options. A team with a lot of bats and not a lot of gloves/arms is going to have a lot of exciting games and find itself on both ends of the 10-7 games quite often. A team with a lot of gloves/arms but a lack of thump at the plate it going to find itself dancing around a lot of 3-1 games. One team is really fun to watch, but ultimately disappointing. The other team is the 2010 Giants (so, yeah, still disappointing).
Here's another way to pose the question: you are going to acquire a free agent player. Do you acquire position player for his bat (thereby scoring your team a run) or do you get a gloveman at a critical position or an ace reliever or veteran starter (preventing a run)? The idea is that we obviously want to get a guy who can hit and field, adding both potentials to the club and giving us that much more of an advantage. Seeing how players who can hit and field are typically in high demand, it's going to be harder to acquire those players.
The next step is to look at the players who can do one of the two things, but not both. Good glovemen like Mark Ellis aren't all that hard to find, whether by sign or by trade. The best of the best out there are locked up with their teams, as they also tend to be some of the more elite talents, but there's typically no shortage of glove first guys on the market - they might even be in your own minor league system!
The other side of the spectrum tends to a bit uglier. There are a lot of readily available players out there who can bat but can't really field. Which is fine if you have the DH or if you have a vacancy at 1B. If those spots are unavailable, you'll have to take that risk that you'll be getting Lance Berkman in RF rather than Aubrey Huff in LF. If you're willing to take that risk, there are a lot of doors that could open for you.
There's a sub-group to this group as well, and these are the players that have played competently at positions other than 1B recently and have fooled their managers into thinking they have positional versatility, when the reality is that they're terrible at pretty much all of the positions they play. Talent acquirers will then overvalue that perceived versatility and be willing to take a hit on the overall batting prowess in order to acquire said versatility, and then sign it to a 2-year, $8M contract.
The problem with these guys is that they end up being Ty Wigginton and you get the short end of both sticks.
What remains is the all-glove players. The good thing about these guys is that they're typically cheaper than the all-bat guys, as one would expect, and can even have ACTUAL positional versatility.
By the time we get to these guys, they're usually ages 33-40, and they're essentially known quantities. Without diving into aging curves on fielding, we can typically assume that good gloves will remain good gloves, good bats will remain good bats (at least based on expectations). Difference is, I'm not going to expect Jason Giambi to suddenly be able to play a competent RF. That said, Lance Berkman jogged back out to RF after spending time as a 1B and a DH and made it worth the Cardinals' while. The point is, batting spikes out of older players looking to have nothing left but their gloves are far more believable than Donny DH suddenly ranging to his left at 3B to start the 5-4-3 DP.
On top of all of this, the Rockies have a young pitching staff, and I'd like to welcome them to 2012 by saying "don't you worry about pitching to contact, we've got this covered". Maybe I'm crazy, but knowing that the 7 guys behind him are going to be helping him get outs might just boost the confidence of guys like Drew Pomeranz and Alex White.
Additionally, the general public seems to view strong fielding teams get the "strong team, not the most talented but still hard workers, playing the right way" while sloppy fielding teams are "lacking focus, distracted by the team's poor performance, pressing, trying to do too much.
To summarize all that, the all-glove guy and the all-bat guy (at least the "positional versatility" option) tend to be equally valued. The upside of the all-glove guy is that they might find one of those magical seasons where they inexplicably see/hit the ball well and end the season at all-star level.
This is what makes an Ian Stewart last-chance such a sticky situation. You could go for a Scott-Rolen-type acquisition and bank on a rebound based on good production just one year ago. You could also just stick with Stewart and get another plus glove and pocket the savings,, but for ~$2M, you'll still be banking on the upside potential of a rebound year.
So all of that summarized just says that the Rockies need to be looking for the best defensive options available. That was what the team philosophy: get pitching, get defense, win things. It did, for a little while, too. The team decides to sacrifice some defense for "right handed road hitting" and has the most disappointing season in franchise history.
Point of the story? Get defense. If you can't score runs, you'll never win games. If you don't allow runs, you'll never lose, either. Beyond the Boxscore ran a historical study on this back in the last offseason.
I'd rather be that team that never "loses" and makes every single step on the way to that win absolute misery for the opponents. That'll do for me in 2012.