I don't understand the idea behind that formation. If I'm the opposite coach I ask my #10 to man-mark Rakitic and force all buildup through Mascherano who isn't great on the ball or the wingbacks which means isolation on the sidelines and more hoofs and crosses than ever. Someone else said it in the other thread. If you think Busquets-Xavi-Rakitic isn't enough midfield dominance what do you expect to see from Rakitic-Mascherano? This kind of formation would only make sense if Barca deliberately ceeded possession and sat back to counter yet against a team like Almeria it's a useless concept and against elite teams I can assure you that backline will get obliterated.
Instead of radically changing formations and benching the most gifted players because they are in bad form Barca should concentrate on building on the 2nd half against Ajax with all 3 lines squeezed together as much as possible and high collective workrate by everyone including Messi.
I think the logic is that bayern use it so it is the football bible of how to play. I prefer the curent formation but building play through the midfield, or a double pivot of rakitic and Busquets.