It is pointless speculating how much negative influence O Dea has had because there are so many other variables involved compared to last season.
That said, it certainly won't harm us when we get shot of him and Stearman early next week because they are both tainted by association by what has happened this season.
Personally I'd get rid of O Leary as well, I don't see what he offers. Only one I'd keep is Marge because he's a specialist coach, and one of the best around. Would seem silly to turf him out.