I suspect the answer lies somewhere in between the stats that show we're not that bad and our eyes, which often say the opposite.
Our supposedly shit defence has conceded 23 goals, which is only two more than the supposedly ultra-defensive rags. But the manner in which we've conceded some of those 23 has been infuriating to say the least. I think we owe a lot to Joe Hart to be honest. I've been very critical of parts of his game but you can't knock his shot-stopping.
Brendan Rodgers said any team can defend (or something to that effect). He couldn't actually manage it though but there's a trade-off between attack and defence. The more players you commit to going forward, the more open you're going to be at the back. It also works the other way of course. How many teams have come to the Etihad and been organised and compact, with two banks of 4 or a 4 and a 5, giving us no room to work in front of their goal? Whereas we go away from home and have 7 players up the field, leaving the centre-backs far too much space to cover. There's too much space between the lines which gives the opposition space to play in.
But we looked good at the start of the season and I don't think that Kompany being there was the whole answer. We played Navas & Sterling as wide men but both covered the full-backs. So Kolarov, who we know is defensively suspect, had Sterling covering him. Without that, then the left-sided centre back has to cover, which creates gaps in front of the goal. But with cover in front of the full backs, the centre halves could concentrate on the middle of the park and not have ot worry too much about the flanks. But we seemed to stop that a few games in and it was noticeable that Sterling was coming in-field a lot more. Kompany's absence masked that to a large degree but that, to me, is the source of the problem. Play Toure if you have to but with Fernando/Fernadinho/Delph and behind a three of Sterling, Navas and Silva/De Bruyne.
You don't have to go all-out defensive; just make sure all the bases are covered.