The context being missed though is the roster we had during that times. For example, when Walker was here, he needed to play, there was no one else, yet Doc refused to play him. The result? He ran Paul Pierce to the ground, who then ran out of gas during the playoffs... very unavoidable. To add insult to injury, Doc constantly played Scal as a SF too much for anyone's tastes, and he was pretty awful in that position.
Moore should've played a bit more last year too. Dooling wasn't any good for us as a PG. and when Moore got the opportunities, he at least was a bit decent.
You put a vet, who are worse than Walker and Moore, and I'd guarantee you that Doc would've given them playing time.
That's just the way he's wired. Now, if a rookie who's actually good, like Sully and to a lesser degree Baby, he'll play them some. But sometimes he's too stubborn when roster situation dictates he should've used some rookies to fill some roles regardless of their competence.