Paqueta behind the strikers might get easily wasted by having a LB with a wooden leg and Abate on the other side + Baka and Kessie in midfield. Close on Paq and it's game over, coz nobody else will create anything.
With the 4-2-3-1 I guess will try to use width and Biglia's long passes, while also having the option to play vertically to Paqueta.
The formation is OK, as could any other be. It all depends if the players will execute coach's ideas. Gattuso might not be a mastermind, but many of the games we've lost because players clearly failed to deliver on the plan.