Yes I would expect that but the visual acuity obtain is still pretty good.
Your main problems however is the amount of anisometropia which is outside the limits for a class one. (In fact your outside the limits for a class two - 3 diopters)
I have no idea how they came up with these values and I would be surprised if there is any evidence based medicine to justify their stance.
What optican did you go to? Specsavers? surely the optom must have read and advised you about your anisometropia.