It's not preconceived. When he's played then he's been poor.
They're might be good reasons such as lack of confidence due to injuries or poor/no coaching (which was f*cking unforgivable) but he was poor nonetheless. Maybe staying fit and getting some sustained coaching from Gallagher will do him good and we'll see a good, solid keeper.
Steward was very good and made some excellent saves over the season so he's got credit in the bank at the moment. If he can't make the grade this season then Simo will drop him.