Explain to me why you give Butler 3/30 and trade Donaldson for a much lesser version and prospects in the same offseason.
Firstly, let's at least note for the record that Beane has utterly devastated trade partners when he makes an established player for prospects move. Do people realize how fast Mark Mulder fell apart after he was traded to STL? He was worth 0.5 WAR over 53 starts over the next four years. Haren was worth 12.5 in three years with the A's, and then traded for a package that included Carlos Gonzalez (THAT trade was indefensible, where the A's trade for an established player. Gonzalez was simply rushed too quickly), Brett Anderson, who has been killed by injuries, and Chris Carter, who would probably be a pretty great DH if he were used properly (and not flipped for a mediocre SS in Lowrie, but again, I'm only defending the established player for prospects deals here). Rich Harden also broke down pretty quickly after the A's dealt him to Chicago, which was the trade that netted Harden (as well as a couple of guys who went nowhere).
Swisher was dealt for Gio, and immediately had a bad year with Chicago, although he bounced back with NYY. Billy Taylor absolutely fell apart after Oakland dealt him. Andrew Bailey? Dead. Ben Grieve? Dead. Look at Cespedes' slash line for last year. Look at what he did for Boston. Turrible.
So I'd keep that in mind. And I'd also keep in mind that while some of Beane's announcement to the press was bull#### (they're a lot closer than "11 games" to the Angels in terms of pythagorean standings this year), he did mention some worry about this current team "deteriorating." If you want to make the inference, he thinks Donaldson's deteriorating.
He's the #1, pound-for-pound, undisputed champion of baseball GM's in terms of getting the most out of what he has. It's almost impossible to conceive that there isn't some hidden angle here that he isn't playing.