Gregg Popovich will occassionally waive the white flag of surrender when his team isn’t playing very well, preferring to rest his aging roster instead of having them grind during an ugly loss. Case in point, last night in Houston. Per “Tim Duncan and Spurs fans got the facts-of-life message from Gregg Popovich on Thursday night at the Toyota Center and spent the entire second half of a 105-85 loss to the Rockets sitting on the bench. And it was the right thing to do. ‘Down 18, third game in four nights, on the road,’ Popovich said. ‘We weren’t playing well. I’m not sure how many times I want to be down 18 in this shortened season and work Timmy, Manu (Ginobili) and Tony (Parker) to work us out of that hole. Not this early in the season. ‘Later on, depending on our situation, it might make more sense. But at this point, it was a great opportunity to treat it like training camp and get a lot of the younger kids out there and treat it like a practice.’ Duncan also happened to shoot 1-for-8 and grabbed just one rebound in the first half as the Spurs were falling behind 53-35. But the Big Fundamental’s 15 ½ minutes of playing time had less to do with in his ineffectiveness than the blink-and-you’ll-miss-it schedule that just never stops. When the Spurs get back home to play the Jazz on New Year’s Eve, it will be the first of six games in nine nights. So especially on a team where Duncan is 35 and Ginobili is 34, discretion will have to sometimes be the better part of valor this season. It’s just one more of the twists and turns in the unusual 66-game, jam-packed season that everyone – players, coaches and fans – is going to have to learn to accept.”