Maybe I misled a little, I don't think there should be line changes. Obviously it should be a gradual substitution pattern where you bring the subs in one or two at a time, to keep some continuity but there will be plenty of minutes for the whole second unit to play together.
Plus, having a whole second unit in there instead of keeping a starter or two in probably won't backfire when the bench you're bringing in has Tayshaun Prince, Glen Davis and Rasheed Wallace, three guys who started for the last few months and playoffs this season, in the frontcourt and a year-under-his-belt-in-Boston Stephon Marbury and Eddie House, returned to his role of 8th/9th (instead of 6th) man with a lot more open looks in the backcourt. Big difference from Pruitt, House, TA, Powe and Scalabrine or some of the other combinations we've had. A couple years ago, when our bench had Delonte, TA, Ricky Davis, Al and Perk, it was a pretty solid second crew that let our starters get some actual rest.
Doc's problem, in my eyes, was trying to turn three bench players (Scal, Marbury, House) into a second unit by throwing TA and Moore out there with them. If the second unit features five competent NBA players, I don't have any problem with an entirely fresh second five playing together against another team's bench players. We'd be extending leads with that crew almost every night, not trying just to maintain them.