You forgot one thing about the Rose example and that is this: Duncan played 38-40 mpg in those days. This season, he'll be playing 28-30 mpg. While Splitter, even if they eventually end up starting him, probably wouldn't exceed 28 mpg (and even that is probably too high). So that would leave plenty of time for Blair and Bonner to play together.
It's so obvious what needs to be done to fix the big man rotation. They need to trade Blair. Let's be honest, he's the only one they might trade anyway and he's the one who's in over his head in his role. Something like Blair, Green and a 1st for Patterson, Adrien and a 2nd would make sense and alleviate many of the current problems.
Short of that, they just need to pick their poison. Either they go with as much balance as possible, which means having a defensive liability at power forward on the floor at virtually all times or they don't go with balance, which means having two defensive liabilities manning the power positions simultaneously.
Looking at the projected rotation, how can they continue to feed the team and the fans this garbage about "getting back to 4th-7th defensively"? Let's say Leonard, once Neal returns, is generally the odd man out. They'll have gotten worse in the backup back court defensively, by replacing Hill with Ford, they're already worse at starting power forward, while only definitively improving at back up center. And on top of that, they don't even have five bigs. Yet they want the players and fans to believe they care about defense.