I had asked for the specific team salary numbers, including cap holds, on San Antonio's books. Steve Kyler tweeted them out earlier today, and assuming they are correct, and they probably are because his team is good about these things at Basketball Insiders, Duncan and Ginobili would have to be playing on maybe $3M or so each (assuming one was res-signed using the room MLE and the other with the cap space not needed for Aldridge's max contract).
View: https://twitter.com/stevekylerNBA/status/614855288928215040
And that would mean renouncing Danny Green, Cory Joseph, Marco Belinelli, and Aron Baynes. If they dump Splitter and Patty Mills on the Cavs, they clear $12M more, giving them $34.5M in capspace, which they could use to sign Aldridge to a max contract ($19M), plus re-sign Duncan, Ginobili, and one of their free agents (presumably Joseph since they would be losing Mills, as well as because his cap hold is low enough that they could retain his Bird rights before re-signing him, allowing them to go over the cap). Then maybe you could re-sign Belinelli (though not Green) using the room MLE. Or another free agent on the open market. But the math here is really tight to keep Duncan, Ginobili, Joseph, and Belinelli.
The team's vaunted depth, so important for an aging team, would be severely affected. Given that the old big 3 would be another year older, I don't see this team as a particular threat. I wouldn't pick them in the West, and I certainly wouldn't worry about strengthening a potential adversary if I were the Cavs.
It's tough to go the "build capspace" route in building a team, since you typically need to decimate your depth to do so, and it usually takes a year or two to build up the bench again. Miami of course made it work, but they were able to sign the clear cut best player in the game, which Aldridge obviously is not.
Maybe I am missing something though, so please others chime in if I am.