Send Walker and Pruitt down there with him. Pruitt to stay in shape since Rivers has him buried and Walker to get some humility to go with his talent.
Good move to get Giddens down there, anyway.
Pruitt will be playing before long. Clearly Doc and Ainge like him, but Doc has always made a point (to great success) to not put young guys out there before they are ready. I expect him to be joining the rotation in some form by January, if not sooner.
For Walker, I don't see how playing in the D-league against inferior competition will teach him humility. I think it would be more likely boost his ego, since he would likely be one of the more dominant players down there.
And for the record, I actually think in general Walker is a very humble person. From all I have heard and read about him, he is very down to earth off the court. Of course he is perhaps a bit (or more than that) overconfident ON the court. But I think the best way to rectify that is to have him sit on the bench, and have Pierce put him in his place in practice.
Anyways, I think this was a no-brainer with Giddens. There was no chance he was playing up here, and he could certainly benefit from playing more. Not to mention, he is the guy, who might be able to benefit from some off the floor humility that the D-league can provide. Just to show him why he needs to work so hard to stay in the NBA.