Interesting graphic.
I think the space between the CBs might have a lot to do with the time they spend there when we have the ball - mainly when our keeper has it.
Our general style when we have the ball at the back is for the FBs to push way up like wingers and the CBs to split off towards the flanks.
There's no way Kosc/Sack would be just hanging out near the sidelines with Aguero and Silva sitting in the middle, that's madness and would've resulted in 10-0.
Most interesting watching Ozil - remember in that game he was 'playing on the left' according to pretty much everyone, but as he always does, regardless of starting position, he is floating side to side, and surprisingly spending the vast majority of his time roughly in the middle in this half in particular.
I really think this Ozil on the left vs in the middle is a non-issue. Wherever he starts he plays his game how he likes, moving side to side all day. It's really about the movement of the players around him - as someone else said earlier.