We've been here quite a bit in the past...and to win through the 'black 'n blue' December through the playoffs, a team must also be able to run the ball. You run the ball much stronger with the double tight end formation. The blend is a factor also, as the team has attempted to take the percentages up to the 50% area in pass to run. Of course with Dallas, the passing will dominate somewhat, due to the terrific completion percentage by Tony Romo.
That stated, I like the concept of keep a defense on it's heels in thought, and wearing them out trying to catch up to a conintual barrage of shifts to that same 3-receiver sets. That will catchup to the secondary and provide a tendency towards late game 'homeruns' and huge plays by Felix as well. Then let Marion pound it out in the double tight end for closure. You still have two receivers rotating and Witten/Bennett to contend with.