I think Raffa is a cleaver football brain and we should trust his judgement in the systems that he employs (both Zone Defence and/or 4-4-1-1 for example).
I read many posts stating that these systems do not work and should be changed, but I don't think that we have seen these systems played properly by the players and therfore we should wait to see these systems mastered by the players, and then we can make a proper judgement.
It may or may not work, who knows, but I trust Raffa's opinion. The point is the players will understand it with repetition, and then we may find out it is unbeatable.
Let's hope they start on Sunday...