Im not saying what you are trying to imply?
If you mean match to match, then maybe we have performed better in 'peak' performances (becomes quite subjective at this point I guess... Especially as we've not seen him in a 3421 yet). However, over the course of the season (especially in Europe and early season when the likes of Dele, Eriksen & Sissoko weren't up to speed) we have most certainly been weaker for his absence.
He'd have been useful at Old Trafford, Stamford Bridge, Anfield and away at Monaco for starters.