As mentioned, the trade was criticized because it may have been the right trade but it was made at the WRONG time.
At the time, the Celts were the top team in the East and were firing on all cylinders.
Trading away their starting center was not the smart decision to make.
This was about messing up the chemistry in 2011, not how things are today.
I think everyone felt that Jeff was the most talented player in the trade but everyone felt it was still the wrong trade to make, and it was.