The A's give away something for next to nothing

The Oakland A's just traded their best pitcher, Rich Harden, along with useful swingman Chad Gaudin for four mediocre prospects from the Cubs.
Harden has been frustrating in his 4+ years in Oakland because he never stays healthy. But when he is healthy, he's dominating in the way few pitchers can be. That said, I'm not sorry to see him traded and would bet he'll be on the disabled list within a month.
The problem is not that they traded Harden -- it's that they got almost nothing for him. Rookie righthanded starting pitcher Sean Gallagher looks like the best of the 4 players they got, but he appears to be at best an innings-eater, not somebody you really want making a postseason start, even in his career year.
The other prospects are similarly flawed. Outfielder Matt Murton has bounced back and forth between Chicago and AAA and has never established that he can hit major league pitching. He might stick as a fourth outfielder, but doesn't seem likely to become a starter on a good team.
Catcher Josh Donaldson had a nice year at low-A in 2007 but is struggling at high-A this year. He's an offense-first catcher, so if he's not hitting, what value does he have?
Eric Patterson got moved from 2B to OF because he couldn't handle the position. And like Murton, he hasn't hit major league pitching in numerous short trials.
If Gallagher is the main player they wanted, the question is: why? He's not as promising a starting pitcher as Gaudin. And Oakland's farm system is loaded with pitching talent. I can see trading Harden for a guy with the potential to be great. But this guy -- all four, really -- has the potential to be adequate.
In short, the A's gave away something of value -- Harden and Gaudin -- for almost nothing. Boo.