From a playoff perspective, the impact is all over the place. So I guess it's just a matter of schedules and certain games
The logic on this is simple. In the 12 personnel the defense has to assume you are trying to run ball and must match up with a run stopping defensive package.
Passing out of this is not only a surprise, but they dont have the personnel on the field to effectively combat the passing game. This also allows for max protection of the QB's which gives time to get the ball out. More one on one on the outside.
If you have two good TE's that can beat linebacker and safeties you can really make them pay. This is what MM is going for with Schoon and Fergy.
And with both TE's being good blockers you can also run well out of the 12.