Is Tommy Hanson a cautionary tale or a success story for the Cardinals' top prospects?

The Winter Meetings aren't quite here yet, but the trade market's already getting interesting: The Braves traded Tommy Hanson, in 2009 one of Baseball America's Top 5 prospects, for a reliever who throws baseball's only jump shot. I am a shallow, self-centered person, so my immediate response was a few seconds of pitching-prospect chills, St. Louis's fastest-growing psychosomatic baseball response.

Really impressive young position players are received with awe; really impressive young pitchers are received with a hushed mix of awe and terror. I don't think it's just because of the injury risk—it's because pitchers' skill-sets seem to fluctuate so rapidly and randomly that it's hard to enjoy a 100-mile-an-hour fastball or a letters-to-dirt curveball without wondering when it's going to vanish, and when that same pitcher is going to turn into a finesse guy with weirdly similar results.

You get those shifts for position players—Reid Brignac's conversion from all-bat-no-glove shortstop to all-glove-no-bat shortstop before reaching the majors is my favorite example—but you don't get so many of them; the threat doesn't seem so omnipresent. Hanson at 22 showed a great fastball, preternatural poise, and fully-formed results; Hanson at 26 is a nibbler whose still-solid strikeout rate seems to inspire more suspicion than a bad one would.

That's pitching prospects, I tell myself. But if it's a cautionary tale for Cardinals fans waiting on Shelby Miller, Trevor Rosenthal, Carlos Martinez, Tyrell Jenkins, Michael Wacha, et al, it might be for a different reason entirely. It might be because Tommy Hanson was kind of a success.

From that No. 4 prospect, the Atlanta Braves got one season that Baseball Reference—otherwise down on him, relative to FanGraphs—rated as nearly three wins above average, in a season in which they were contending. FanGraphs credits him with 10 WAR over 108 starts. For all that, the Braves paid him about $2 million. And now they have the use of an equally cheap above-average reliever who is somehow allowed to jump off the pitcher's mound while he throws. Which is nice.

In that sense, then, Hanson served as a pitching-prospect-corrective for me—if his career seems incredibly disappointing, I'm maybe overestimating what it takes to make a top prospect into a success.

When we see a top prospect finally play, we badly want the promise they've shown us to become something we can count on; I watch Trevor Rosenthal beat Bryce Harper and I want that to be something I have to look forward to for a while. For most prospects that's not the case. The scouting reports we've grown used to will become outdated; they'll put on weight and gain power or move to third base; they'll turn into somebody's reliable and boring fourth starter.

In aggregate, though, prospects are every bit as valuable as we believe they are—just for more pragmatic reasons. When teams are paying $5 million a win for B.J. Upton, they're making Jon Jay money. It might not be as romantic as imagining Tommy Hanson (and Shelby Miller and Carlos Martinez) winning 200 games and postseason-dueling other 2009 top prospects into perpetuity, but it's not as bad as forgetting that Tommy Hanson, whatever he is now, was briefly a really good pitcher.