Zone defense of the Mavs can play a big factor in containing Wade and Lebron.
I can see Marion playing a similar role as Deng in containing Lebron and forcing him to take the outside shot more often than not, but I don't see one player on the Mavs doing that to Wade 1 on 1.
Ppl may have this bad series of Wade in their recent memory but he was the best player against Boston when he was defended by Ray Allen and Delonte West. Now he's going to be defended primarily by Stevensson and Terry so stopping him should be a priority for the Mavs as a team, not to mention the historical reasons.
Dirk has to dominate offensively as he has been doing the whole playoffs. Looking at the matchups there is no reason to think that he won't.
Lebron will have his numbers and theres also not much that can be done about it.
If the Mavs can limit Wade they will win this.