I really doubt Henry needs much of an explanation about why Reddick was dealt.
You guys are acting like the Sox didn't know what they had, or somehow should have done more due diligence before trading Reddick (and Lowrie).
Over 3 seasons of playing time, Reddick had 403 PAs in Boston, in 143 games. His numbers were .248/.290/.416/.706
In addition, he had 2003 PAs in the minor leagues over 5 seasons. His numbers were .278/.332/.500/.832.
Last year, during his first 182 PA he had this slash-line: .307/.357/.515/.872, with 6 HR and 25 RBI. Hell, he could have been an All-Star if those numbers kept up. They didn't.
The Sox knew what they had. He might end up being an .832 OPS guy in the majors during his career. That would be a nice career. If he ends up being a regular .900 OPS guy then the Sox will have been wrong, but if he returns to his career norms then it's not a franchise crushing move by any chance. Now, if Miles Head or Raul Alcantara turn into better than average pieces, then it will be obvious the Sox "lost" the trade.
Until we see how everything shakes out, I'm very comfortable withholding judgment.