I have heard two explanations defending the FO for its inaction at the trading deadline:
1. They didn't make any moves because they were counting on the healthy returns of Pedroia, Ellsbury, VMart and Beckett in the second half, and that was better than any possible acquisitions.
The problem with this argument is that none of those guys addressed the bull pen problem.
2. The FO "knew they were going to be without two of their best three position players for the rest of the year. Can't fault them for not wanting to give up any assets for that."
Quoted from your post.
Well, which is it? One thing that both explanations have in common is that they excuse the inaction of the FO. Curiously, these explanations seem almost diametrically opposed to each other. We really started hearing explanation #2 after the reasoning in #1 didn't pan out. BTW, #2 is based on a false premise. Youkilis did not go on the DL until after the trading deadline had passed, and Pedroia was expected to recover and resume playing.
I find it amusing that people look for excuses for the FO. This is big business and they are grown ups. Hopefully, they are critically analyzing their own performance more so than we are doing here. That is what good businesses do.