Quality take.
In the second quarter, I thought Pop should have gone back to Splitter and let Duncan rest until halftime. Even when Pop pulled Duncan late in the second, he went to Bonner instead (he then changed his mind a few seconds later after the Blazers went small).
In the fourth, even though things were rolling and the Blazers were small, it would have been nice to get Splitter in there just to build off his very good effort. True, he wasn't needed but at this point I'm for Pop force feeding Splitter as many minutes as possible.
But overall, you are probably right. Unless Pop was specifically thinking about giving Splitter extra minutes, the flow of the game didn't deem it necessary..