TPE isn't cap space. It's the ability to take back $12M in trade without sending out players to match salary. They don't need FAs to come, they can trade for guys under contract for years to come. For example, supposedly the Nets want to get rid of Marcus Thornton. They guy had a 16 PER last season, even with a FG% under .400, and makes a reasonable $8M with one season to go on his contract.
Oh . .. thanks for the clarification. Clearly I don't understand Bulls situation . . . don't mind me, I'll go back to lurking the Bulls forum.