In the playoffs, you want to play your best 6 players heavy minutes, and beyond the 8th man, minutes should be very scarce. The 2012 Spurs had a lot of success in the regular season and first two playoff rounds playing 10-11 guys, but it has never been a winning recipe and that was proven again in the WCF.
The problem is that, of the Spurs' 8 best players, 4 are wings. Duncan, Parker, Ginobili, Leonard, Splitter, Jackson, Diaw, and Green are the 8 best, but only one is a PG. If Pop is willing to try giving Duncan and Ginobili big minutes in the playoffs (what do you have to lose?), I could see a 7-8 man playoff rotation that doesn't include Blair or Bonner at all, with at least one of Parker and Ginobili on the floor at all times to handle the ball; none of the potential backup PGs are in the top 8. If it didn't screw up the starting rotation so much, I could see Green dropped too if he starts to crap the bed again.