GB, I hear ya, but not sure there is a blueprint set in stone. All players are different and react differently and have to be treated as such. In an ideal world everyone should be given time. Its a business, however. When you choose to go out and buy a host of foreigners its not really always practical as a competitive club to then afford them 3 years to settle in. Fazio and Soldo are vets. When Chelski signed Eto last season on a 1 year deal, even tho he had never played in the PL or in England before, they must not have been too concerned about the prospect of having to 'ease him in very gently'. Regardless of how he actually turned out, their strategy up front must have been that he'd come in and hit the ground running. Part of the evaluation when/before buying a player must be a projection of how quickly you feel they will adapt. When we bought Soldo I doubt we felt it would take him this long to settle in and make an impact regardless of the circumstances that have transpired at the club.
Eto'o is probably a bad example as Mourinho had worked with him before and Chelsea can afford having someone like him on the bench just in case.
Some very senior/talented players have failed as well. Veron, Schevchenko, Sahin, Aquilani. Some never adjust. Soldado looks like he has changed his game to something we can use.