a 4-3-1-2 or 4-3-2-1 Has so much offensive players in the center, that it doesnt need offensive fullbacks, that would be very un-italian.
You need physical fullbacks that stretch the play, but they dont have to make the backline
The point of the formation is that the cam and ss are the creative sources, and then there is the rocksolid mid3. If we switch to pogba-marchisio-vidal, we got a very very strong mid3, with vidal and pogba able to be aggressive and press forward whilst marchisio keeps the shape intact. Because of the more defensive fullback, there will be plenty of space for pogba to move into, for his killer early crosses to llorente.
You need to step away from the idea that the CB is actually dolan, and the rest of the team are poachers in disguise.