It's not immediately clear what role Dickey is expected to play in the bullpen next year, but I don't think it necessarily has to be clear at this point. It's never a bad thing to go into Spring Training with more Major League caliber pitchers than there are available roster spots, and the 'pen that the Twins looked to be ready to go with wasn't exactly filled with 7 All Stars anyway. There's room for a guy to get pushed out by Dickey if it looks like he's better. If he's not, then the Twins can get rid of him instead. I can't imagine the money is going to be much of a deterrent.
This was a quirky little Christmas present from the Twins to those fans who were excited by the Dickey signing last year only to see him snatched away by the Mariners. We'll see how he does when the season rolls around.