Tim Duncan probably does not play all-out every night like he did earlier in his career. He is content to let Tony Parker and Manu Ginobili do much of the heavy lifting.
He does raise his game in the playoffs. He will again.
The team as a whole does not show the energy and fire of past Spurs teams. Part of that is because the regular season does not mean a whole lot to them. They have had home-court advantage and lost in the second round. They have been the #2 seed, and cast aside the #1 seed in the WCF with little fanfare.
Given how much better they are on the road this year, HCA likely does not mean much to them. That said, their mediocrity at home, which ought to be their comfort zone, I think does speak to their complacency.
The danger in trying to "flip the switch" is that things like team cohesion are developed over an entire season, not a few weeks in April and May.
And while their lackadaisical at ude contributes to their underwhelming performance this year, the fact remains that aside from the Big 3, this team is composed of aging role players who are nearly totally spent, and marginal NBA talent which only looks competent because of the system. Their lack of athleticism, lack of rebounding, and unexceptional interior defense preclude their reaching an elite level. These are structural problems with the roster unrelated to their effort and focus night in and night out.
So perhaps their lackadaisical at ude stems in part because deep down they know they aren't truly good enough to win it all.
And perhaps the inattention to what have been obvious roster needs for a couple of years now betrays that team management no longer has that full commitment to winning. If leadership is not committed, then neither will the team be.