I agree that Yaya is much more of an attacking threat when pushed forward later in the game. The vast majority of his goals are scored in the second half, which applies even when he has started in the forward role.
However I really dont like the 4-2-2-2 system which employs Silva and Nasri split left and right. It seems to me that neither of them are completely effective in those roles. I would much rather see us play the Sunderland formation, with Yaya pushed forward and Silva given a roaming role. I just dont think Nasri is doing enough to justify a starting position, when all our midfield players are fit, and would rather see him used from the bench.
However I really dont like the 4-2-2-2 system which employs Silva and Nasri split left and right. It seems to me that neither of them are completely effective in those roles. I would much rather see us play the Sunderland formation, with Yaya pushed forward and Silva given a roaming role. I just dont think Nasri is doing enough to justify a starting position, when all our midfield players are fit, and would rather see him used from the bench.