I think a lot of people have an unrealistic view of what the academy will actually bring.
We are expecting it to promote players who at a young age are worthy of challenging some of the best players in the world or the PL. A players development will take time and we are expecting them to replace a proven player in the first team and at the same time not hinder our results.
Look at the case of Denayer. There is no doubt in my mind that he could do the same job in this squad that Demichellis does. In fact he would probably be an upgrade at the moment. However, having a young CB, who has the potential to be a first team regular for us, sit on the bench for most of the season is not beneficial for him. At the start of the season Mangala, Otamendi and Kompany were all better players and by starting Denayer over one of them would have been detrimental to the side. He's got a good loan to a CL side and when he comes back after two good loan deals he will be ready. In fact, it will be perfect timing with Demichellis gone.
Joe Hart is the best example of this. The season we loaned him to Birmingham he was not as good as Given. However, we could have done we keeping him in the squad as you need two good keepers and if memory serves me right, Given was injured at the back end of the season and we had to get Fulop on an emergency loan who played in some key fixtures. The facts are though that he returned a much better player, he got into the PFA team of the season and quickly dislodged Given as our number one.
Only regular game time can help youngsters reach their potential and they are much more likely to get that our on loan. The sides who challenge for multiple trophies tend to rotate a lot more and rely on their key players so it would be extremely difficult for a young talent to break through straight away.