Not to rehash the same old topic but something that goes into this is getting players that your coach will trust come playoff time. Clearly the bench that Doc has been saddled with is full of players that Doc doesn't find trustworthy to use in pressure situations like the playoffs.
If that is the case, why re-sign Tony Allen when last year it was evident that Doc would never use him in a playoff atmosphere? Tony's healthy and not being used because his coach doesn't trust putting him on the court with important games on the line. He feels the same way with Moore, always did with O'Bryant as he was highly critical of the kid from the get go and unlike the year before with Baby, Giddens and Walker showed him nothing to trust in.
This is a team contending for a championship and saddling your coach with 6-8 players throughout the season that your coach will never trust to use in pressure situations, big games, or the playoffs is incomprehensible to me.
Ainge brought back one player that Doc trusted and that was Eddie. Tony, POB, Moore, Giddens, Walker, Pruitt, and Marbury are all players that Doc has no faith and and really probably shouldn't. If Ainge had brought in players that were proven vets that Doc could have built a relationship with and grew to trust, things would be quite different right now.