Now that Sean Gallagher has been confirmed as the PTBNL, reality has hit: The A's got something of value, and the A's gave up something of value too. As someone high on Gallagher at the time of the Rich Harden trade, I'm not going to play "sour grapes" and analyze this trade as "well I never liked Gallagher much anyway." However...There are some additional reasons I think the trade is still, on balance, a very good one for Oakland.
* The A's insisted on, were excited about, and were willing to trade Harden for, a pitcher, in Sean Gallagher, who threw 95MPH and had no known history of "issues" that might predict issues with his development. But that's not who the A's traded. Gallagher did not throw 95MPH after that seductive first Oakland start, and considering that he came with only spotty command (good in the minors, but hardly razor-sharp in the bigs), and a curve that only he and hitters seemed to like, Gallagher's drop in velocity represented a problem with the one and only tool that really made him special.
Couple that with behind-the-scenes issues -- be it with his attitude, his work ethic, his conditioning, we don't know -- clearly something soured Oakland on the same guy on whom they had such great hopes a year ago. There just isn't such a thing as "Sean Gallagher, period." The Gallagher the A's acquired was simply worth a lot more than the one they dealt. It happens. But the A's did not deal a potential #2 starter with a 95MPH fastball, even if that's what they got a year ago.
* I don't think he's a .300 hitter, but Scott Hairston appears to be capable of hitting 20 HRs and stealing 20 bases. That won't win you any MVP awards, but consider how important an upgrade that offers the A's lineup in the near future.
Forget 30+ HR hitters; how many 20+ HR hitters do the A's really have going forward? Jack Cust. That's it. Sweeney hasn't shown that kind of power, Buck hasn't reliably shown that kind of ability, Barton doesn't promise that kind of power. Ellis, Suzuki? Not quite. How about 20 SB? Buck could steal 20 bases if he got on base enough, but can you write him down for a 20 SB season? Not at this point. Sweeney? No. Ellis? No.
In contrast, look up and down the current' lineup and you see potential 20+ HR threats in Guerrero, Hunter, Napoli, Rivera, and Morales, and 20+ SB threats in Figgins, Aybar, and Hunter. The A's don't have enough "decent power threats" or "decent running threats" up and down their lineup and Hairston actually aids both causes.
As the A's try to build a respectable offense again, don't take these skills too lightly. 30/30 is terrific but 20/20 is big too, because you won't easily find or afford many 30 HR guys or 30-40 SB guys, and even when you have one your offense is still lacking without 2-3 other "20 HR" and/or "20 SB" guys -- but is also pretty potent with 2-3 of those added to the mix.
* A phone salesman is peddling a product, and just needs 1 out of 20 people to say yes in order to make $100.00. He calls the first person and the person says "no thanks." The phone salesman says, "Dang, no sale." Next to him is another phone salesman, peddling the same product, calling his first number and also hearing "no thanks." The phone salesman says, "Ca-ching, made another $5.00!"
The point is, the second salesman understands that calling is a process. Make enough calls and on average you'll end up with $5.00 for every call you make. Sure, some of the calls will yield $0.00 and some will yield $100.00 -- in fact most will yield $0.00 -- but it doesn't really matter whether a given call yields a sale or not, because if you just keep calling you'll hit those "every 20 calls" that give you your bounty.
Prospects work the same way. If a prospect has a 10% chance of blossoming into a surprisingly successful player, then he's probably going to bust. It's unlikely, for example, that Ryan Webb will single-handedly make this trade great for the and horrible for the A's, and it's unlikely that Matt Spencer will be the reason the Blanton trade was so good for Oakland, such a disaster for the Phillie .
But if you make enough trades that include getting and giving C-level prospects, the reality is that somewhere along the line, someone is bound to be far better than expected, and that the trade will look far different in hindsight than it did at the time. The important things to remember are that this is just bound to happen occasionally and that it is impossible to predict, and so it shouldn't really make that trade better or worse even in hindsight -- because it just happened to be that 20th phone call, and when you trade, or get, 10 C-level prospects over time, you do it knowing that 1 will probably turn out to be really good but also that you just can't know which one, which trade, and that really you're just playing the odds over time.
So probably the best way to judge trades that involve prospects (who aren't headliners) is just to assign them a "10%," or a "20%," in your mind and leave it at that. Sure, one of those prospects from one of those trades is going to blossom, but darned if even the scouts or GMs know which one.