I know I am not Ancelotti... but I really have to question the desire to bring Pirlo to Chelsea. True, he is (arguably) the best deep lying playmaker in the world but I would think that a team with Lampard, Ballack, Essien and Jon Obi Mikel already, one of them could fulfil that role. All 4 of them are more Pirlo than a Gattuso or Kaka, so if he trying to duplicate the Milan style I would go for a more Kaka like player than a Pirlo like one.
I guess, based on his thinking, Lampard = Seedorf ; Essien = Gattuso; and right now it was Malouda, Joe Cole and Kalou for the Kaka role. Now that he selling Kalou, I guess Deco might get a bligh there (if he doh leave.) or the new 'winger' they buy.
But where does that leave Ballack? I think Ballack coulda done the Pirlo role unless he is just backup for Lampard.
The only way I see it is that maybe Mikel still being groomed so he figure Pirlo will be able to be the person to show him how to do it properly, since Mikel is definitely not a Makelele and have talent to be a more creative player.