Well, that's part of the confusion with the Red Sox trade - they already took cash, but the deal still wasn't complete.
The Phelps deal may actually be the deciding factor - having added his salary, they may want the Sox to send more $ to further lower their tax hit on Workman and Embree. That won't work with the Pirates deal, though it would still be real money. It's possible the "and" in the description of the Pirates deal should be "or." I feel like we might still get a player there, but it won't be anyone ranked higher than the three guys we are apparently sending to Milwaukee. I mean, it was for Austin Davis!
I forget who said it first, but the feeling was the Phillies had to include Seabold to get the Sox to send the $. Straight-up they could have sent a lesser prospect.