I was writing a piece for about.com earlier this week looking back over City's season and where they had perhaps missed some opportunities, both in individual games and in the context of 2014/15 as a whole.
There were certainly individual moments that set them back: Stoke (h), Arsenal (h), Chelsea (a) and Burnley (a) being prime examples, but what was noticeable was how devastating their return in January was to their title hopes. This of course came on the heels of their relentless run in late November and December where they had the chance to set a new record in terms of consecutive wins.
They fell one short thanks to the draw at home to Burnley, but quickly rebounded at home to Sunderland on New Years Day. It was this point that they went joint top of the table, their win good enough with Chelsea's 5-3 defeat to Tottenham later in the evening to leave both teams with 46 points.
This meant that City had clawed back a not insignificant eight point gap on Chelsea to leave them in prime position for a run at the title at the turn of the year. Well, we know how this has played out (barring a miracle) over the ensuing months.
Following the Sunderland game City had the following four Premier League fixtures to take us into the first weekend of February: Everton (a) 1-1, Arsenal (h) 0-2, Chelsea (a) 1-1, Hull (h) 1-1. Three points from a possible 12. In contrast, Chelsea took 10 points (the only dropped points being against City). A seven point swing in four games undid all of City's previous good work:
The above chart (as basic as it is) illustrates this, showing how City worked their way back into the race only to fall away dramatically. There have largely kept pace since with Chelsea (which demonstrates that Chelsea themselves have stuttered) but to no avail.
Having come back once that January stumble looks to have been too much for City to mount another attempt.