What players do you require for the 4-3-1-2?
Camo played in such a system in the past, so has Poulsen, so has Diego, and we had a glut of CM's like Tiago and Marchisio. Our wingers such as Marchionni and DC were mediocre. Giovinco wasn't given a chance. Nedved has always been better in the middle like he was with Lippi, and I think he was held back in his role under Capello. With Ranieri, Pavel was just getting too old.
To be honest, we didn't really have the players for either system. We had too many garbage players and with an inexperienced manager, trouble was bound to occur.
If you recall, there were several complaints against how we couldn't create shit under Ranieri. People tend to forget that. And without Del Piero, I think it's fair to say we would have created far less than we did. So IMO, this 4-4-2 stuff is an illusion.