As someone who, for whatever reason, enjoys watching Tyler Greene play baseball, I'm in favor of the trade that sent him to the Astros for probably-cash. As someone who wants to see the Cardinals win baseball games—well, I think they could have managed the Tyler Greene situation a little better than they did, but the Cardinals giving up a guy who's within a few runs either way of replacement level isn't worth my dipping into the dry powder, outrage-wise.
What the Cardinals did lose, in trading Tyler Greene for probably-cash, was a little depth—they've put themselves within one trip to the disabled list of Pete Kozma, instead of two, basically. That's not ideal, but it's not the kind of depth we'll talk about when we talk about how the Cardinals have competed this season.
So let's talk, for a minute, about that kind of depth. The Cardinals have competed this season because they've come up with a remarkable amount of above-average depth. Near-star depth.
Allen Craig is the obvious example, here—through some bets on veterans the Cardinals managed to come into the season with a fourth outfielder who was coming off an OPS+ of 151. Thanks to Lance Berkman's knees he's become their first first baseman. Behind him—and David Freese—is Matt Carpenter, who's got an OPS+ of 136 in his rookie season.
Chris Carpenter was replaced by Lance Lynn, who has been Chris Carpenter for four months, now. Even the Cardinals' starting center fielder began his career as the too-impressive backup to Colby Rasmus.
Because both involved Albert Pujols and Tony La Russa the 2006 and 2011 World Series winners will probably be seen, by the next generation of Cardinals fans, as part of the same narrative. From a fan perspective they mostly are, but in terms of baseball operations they represent two very different philosophies.
The Walt Jocketty Cardinals were famous first for developing huge stars and nobody else—J.D. Drew, Rick Ankiel, Albert Pujols—and subsequently for trading whatever else managed to emerge for ready-made reinforcements. The 2006 World Series roster featured Jeff Weaver, Ronnie Belliard, Juan Encarnacion, Scott Spiezio, and Preston Wilson. It was fitting, then, that in 2011 the Cardinals' postseason hero was the rare prospect they'd gotten in exchange for an established star.
But 2012, without Albert Pujols, without Tony La Russa, is that philosophy taken as far as it goes, which is why it's such a fascinating team to watch. Its big free-agency deals, short-term contracts for three veterans with career-threatening injury problems, were predicated on the idea that there were championship-caliber players sitting on the bench, waiting to be pulled from the strategic WAR reserve.
So far, in every way except for the shady alchemical conversion of runs to wins, it's worked—which is why, if the Tyler Greene trade worried you at all, it was probably because he was sent for by the Cardinals' erstwhile Flamel himself, Jeff Luhnow.
This is the anxiety that comes with a truly successful strategy; the Cardinals' all-star depth has been so long in developing, and so broadly successful, that the last thing left to wonder is where and why it will break down. Jeff Luhnow, whose influence on the Cardinals' post-Jocketty success is certain but unquantifiable, makes for an easy focal point for all that concern.
As for Ryan Jackson, Tyler Greene's rangier, less-benighted replacement, he gives the Cardinals another chance to get greedy with the very concept of depth. (But I won't be totally comfortable until they manage to do it without Luhnow...)