ROSTER TALK: Mavs favs for Vogel if no HC job exists. Kyrie handshake deal?

[Chicagojk]

Can someone help me understand the flexibility talk about keeping the 15th spot open?  From what I understand, the Mavs can only offer the minimum.  So the only cost to adding another player if they fill the 15th spot is the releasing of a current player, right?   Am I am right to say in theory this would not create any more flexibility?

So when Marks talks about flexibility is he more thinking about not doing anything before camp when they may sign the last player?   Maybe holding out hope in a slim chance one of these bigger trades happen before training camp.