I have thought about that too , but it isn't as easy as it sounds . Having bon bon on pirlo's place could give much more covering , and probably allow us to play and easily sustain a very attacking trio . Thinking 433 with tevez llorente vucinic , but nobody can gurantee that bon bon will perform as good in playmaking as he does as CB . First , he is good , but nowhere near pirlo level , second being a midfielder means he will probably be marked throughout the match , being at cb gives him much more freedom to move and much more time to choose his paces with tranquility , without worries and usually he doesn't have anyone attached to him through the whole match like pirlo does . It could be tried , but it needs to be worked on heavily on training , players may seem to have good qualities that should allow them to play in another position , but changing just a little your position in the field can effect a lot on the performance of the player .
Personally i would simply put pogba in pirlos place