Cuban is an enigma. He's like a cross between Billy Beane and Howard Hughes.
After the 2011 championship, Cuban thought he could outsmart the new CBA and build a team by shedding contracts and making shrewd deals. The problem was that he didn't have to do so. Players (like Tyson Chandler) could have always been used as bargaining chips, not something to bail on and free up space like a video game. The work stoppage that year really screwed with Cuban's perception of what a good team could look like, while the Heat said "f**k it" and kept their superteam together. Meanwhile, Cuban stuck with guys like Delonte West, Roddy Beaubois, and Brian Cardinal. Ugh.
TLDR; He could have conceivably built (around Dirk) what every other superteam was doing, but was so consumed by the CBA, he went into a shell. He's doing the same now to Luka, who will definitely leave Dallas.
He made the mistake of thinking he was smarting than everyone else. I remember his comments (just the general gist) and as you say, he pretty much thought he understood how the new CBA would drive the cap and people's behavior.