What does it all mean?

[mavsluvr]

A trade exception cannot be combined with a player for salary matching purposes. 

All I'm suggesting is the Mavs could waive Roby and then trade "air" e.g. something like a future 2nd for someone like Roberson + No 1. 

Roberson would fit into the Mavs TE and save OKC millions and millions. Probably not the best example, but that's the idea.

Another example might be Mavs future 2nd for Dion Waiters + No 1. 

Thanks for clarifying. 

A package of [ Lee + Jackson + MIA #1 + GSW #2 ] should get you a high level starter.

That might fit a salary matching package, but can't imagine another team would give up a high level starter for that. But you never know. Will be interesting to see what develops. A lot might depend on whether the Mavs really see themselves as having a good chance to win the title this season. If they don't, I would be surprised if they are willing to give up much of anything in the way of flexibility for a player they would only want if they drastically speed up their timeline. But I've been surprised before! And the front office is probably at least considering the possibilities, just as you are!