My guess is he didn't want to totally alienate the fan base. While the Crash trade was unpopular we at least got 2 first rounders for him and cleared playing time for Henderson. So I think all in all you can at least rationalize that decision but, to trade Jack with no one in the background to develop in those minutes and no 1 st rounders coming back- that could,t be explained as anything other than a bad move.
Another things Jack and Crash were both best when playing at the 3... It's hard to justify spending that much money to 2 players who are both suited best to play the same position. My guess is that Crash had the higher trade value and that's why it was him out the door instead of Jack.