The system could work if he had midfielders who, for sake of argument, weren't Westwood or Gardner. But the midfielders are Westwood and Gardner.
Jedinak is fine, Tish looks promising for the future, but there's nobody at the club you look at and think 'now that's the man'.
Anyway, on the basis that the international break is a good time to change a manager... I'd stick with Di Matteo for now. If the next four games are a disaster (ie fewer than three points) I'd consider getting rid during the October international break.If he survives that, I'd also consider booting him if we haven't got at least a dozen points from our next nine (which takes us up to the November international break).At the end of the season, if he survives that long, we should be top six or his position would deservedly be under threat.