I'd accept 6th yes. I wouldn't be happy with it, but I also don't think that a bad season means sacking a manager who has good potential. Football keeps getting condensed into tinier and tinier views. Changes to any organisation, especially a performance driven sporting one like a football team takes time which everybody seems to recognise and nobody seems to put a figure on.
There's a very, very top class of manager who seems to work wonders immediately. Capello and Mourinho jump to mind, they're short term people - the longer they stay at a club, the worst the results become (though always to a high minimum standard). After this, there are a class of manager that takes a year or two to really build things. We can include Ferguson, Wenger and perhaps our very own Mancini in this. Each of them struggle at the start but eventually conquer the club with their style of football which goes on to great rewards. Mancini's Inter won 3 Seria A's, year after year, whilst getting further and further in the Champions League. It's absolutely no surprise to me that the core of his team went on to win it last year. These are the long terms guys who get you success.
People seem to want the former type of manager - the instant successes. This means that a coach will come into the club, buy a shitload of names, win us the CL then bugger off. This leaves us in a problem - we build a reputation in the game for Madrid type of club with chopping and changing ruthlessly. This is why Wenger will never go to Madrid in a billion years. He is building something with a particular plan at Arsenal, there is no reason to throw that away for a momentary piece of glory with Madrid. Instead, he will stick the course. He'll have good seasons and bad seasons but he knows that his plan is working and Arsenal are becoming more and more of a threat. They would have achieved the holy grail of winning the league using lots of youth players in a system that produces lots of players over time. Wenger will build Arsenal for years to come, just as Cruyff built Barca for years to come.
I don't want the first type of manager as I want a dynasty. Basically, I prefer a marriage with Keira Knightly rather than a one night stand with Jordan.
Due to this, you need to be absolutely sure that you have the right person. Mancini's former record tells me that we have a young manager, who has never finished outside of Europe and has won trophies wherever he has been. Secondly, Mancini plays a very distinct and successful type of football; it's very tactical, at times it is beautiful, and it mixes great passing with great pressing. Thirdly, the man is friends with both the Sheikh and Khaldoon and was one of their football advisors during the takeover so we can expect a good working atmosphere from the club between different levels of management. Fourthly, I think that he's well educated tactically following the great schools of football and his lectures or interviews on the game are always interesting. Fifthly, he's managed very difficult players before in Ibra and Balo successfully, while handling the pressure of Inter (which most people will tell you used to be a death knell). Sixthly, as his tenure here shows, he's more than willing to give youth a chance when needed which will help us in the future. Just as with Balo, he knows how to bring players through.
So, I'm convinced that we have a good manager due to this, and the improvements in organisation and tactics that I have seen since he came here. As he ages, he will also only get better. With this in my mind as proven, we also know that due to our position as a club willing to spend, he knows that if he wins us something he will be a legend in our eyes. He will be happy here and we will worship him.
He has a very rare opportunity as do we. We have (with the exception of Guardiola), the most decorated young manager in the game, who is friends with our board, who has a near unlimited budget. He knows that Khaldoon and the Sheikh will give him the opportunity to build himself a dynasty and become one of the great names in football as a manager just as he was as a player. People are very rarely given this chance, so he will know how valuable it is.
The deal suits all sides. We have an opportunity to build something together, both City and Mancini, to raise themselves to the top table of the game (though Mancini was already there) and long term, sustained plan of how to run our club.
I'm not willing to throw all that away because of a single bad season.