Pop is stubborn. He did it with Finley's last two years here. At least in Finley's case maybe the argument could be made that there wasn't another person on the bench better than him.(this doesn't explain using Finley as a power forward though)
Blair is the current Micheal Finley. He is a guy pop is going to play because that is how he wants it to be. The Bottom line is he is the fifth best big on the Spurs. If you are ranking Centers in the NBA on Talent(injury pron smingery Prone) then Splitter would be a top 12 center and Blair wouldn't even start at center on any of the other 29 teams in the NBA. That is just a fact. He is playing center(Finely played power forward in certain lineups....)
So there is no Justifiable reason why he gets more minutes than splitter, why get gets more touches than splitter, why he gets more shots than splitter. He does because Pop Makes it so.
Again early in the year maybe there was a case that you had no other bigs on the Bench better than Blair. However, with his recent performance and with the recent acquisition a case can be made that if you rank the Front court 4', 5's on the roster it would go like this.
- Duncan (goes with out saying)
- Splitter(facts are facts and he has the highest FG%)
- Diaw (maybe a case can be made here that he has certain weakness and has shown focus problems in his career)
- Bonner(at least he has the potential to hit 3's and for what ever defensive liability he brings to the table and that is something plus he fist in to Pop's professed style of play)
- Blair(he is a defensive sieve against a guys who are longer and taller than him. This whole "he is physical" argument is dead because his rebound rate is headed south, He has a very limited offensive game, LOL a "center" shooting floaters, and he makes way to many "dumb" plays,
So the bottom line question to why Splitter gets limited time.
Because Pop is a wizard and he makes it so. We all just have to live and die with it.