How do you mean as proved by Chelsea? Since Abramovich came Chelsea have consistently challenged at domestic and european level, which is where City want to be.Chelsea were a champions league and top 4/5 league side and they had trouble signing some of the real big players, whats the difference for City. They are not even that. They may have the money but they still have to convince a few more big players to join. As proved by chelsea, money isnt every thing.
It takes time to build any team, but what money can do is rapidly accelerate the growth.
Make no mistake, I do not want City to get anywhere near to the top of english football. But when a club has the will and means to buy anyone (anyone who would then actually sign obviously), that is something to be concerned about in the long run. Which is why I don't see it as a joke that Robinho signed for them, I see it as a possible sign of things to come.