Spatchcocking is taking a whole bird, cutting the spine out, and flattening it before grilling.
Sous-Vide is vacuum sealing the item and giving a tempurature controlled water bath. In this case, you could add a marinade, cook the breasts 75% of the way in the Sous-Vide, the finishe them off on the grill. All the time they would be in the bath, they would not be losing any moisture.
But, if you're going boneless/skinless straight to the grill, I would definitely consider adding the bacon.
BD