Jevi, did it ever occur to you that the problems that the second unit had in scoring and building upon leads last year, especially in the second half of the year when Davis played, was an entire team problem?
I remember game after game after game where the second unit might not expand a lead but would maintain it only to see the starters come in and lose it. I saw Rasheed Wallace forget that he was 6'11" and could play in the post and rebound and hustle for lose balls. I saw Eddie House have his worse shooting year in 5 years. I saw Daniels go down to injury. I saw Tony Allen be pathetic on offense.
The problems you mentioned were endemic of the entire team. The starters gave away more second half leads and lost games than anyone. Across the board the team was awful at defensive rebounding. As for the box out his man comment, that is just plain wrong. Davis boxes out better than just about anyone else on the team. He boxes out so well he takes his man and himself out of the area to get rebounds so that his team mates can get them. The problem is that most of his team mates suck at boxing out and try to use their fading athleticism to grab rebounds and that is no longer working.
I suggest you get a hold of some game tapes from the last 6 weeks of the regular season and take a more careful look at just how this whole team was playing. They were all bad.