I am in no way disregarding what he has done during the past few seasons, he was our most creative forward during that time and deserved every start we get. I'm also not implying he's useless or should be sold, just that, as long as everyone stays fit, he should not start in front of Tevez or Llorente. Concerning his usefullness as a substitute, there are games where a forward like Mirko is more effective, others where Quagliarella should come in, and even some where Giovinco is the best choice. I must admit that I probably underestimated his effectiveness coming off from the bench, and that Alen has changed my mind a bit in that regard.
Thing is, his role as a creative forward has now been taken by Tevez, who, in all due respect, is better in pretty much all aspects, and most of all consistent. Also, his stats from last season are flattering in a way that he has played way more minutes than any of the other strikers, just take Qualiarella for example, who may be a bit frustrating to watch sometimes but is still a very consistent goaslcorer (then again, I might just be fanboying, but his stats certainly support me here).