Is there any reason you think they shouldn't hold you at fault?
Do you deny being in a location without priority?
In that case, is there any reason you think they could contest this?
Well, it doesn't matter what the officer did or did not say. It is nothing to do with him or his views.
This is question of civil liability. If you were encroaching upon his priority then you are liable.
There might be a reduction for contributory negligence to reflect speeding but no more than that.
In any event though, you would have lost your no claims bonus as there has been a claim. It wouldn't matter whether you were vindicated or not.
Can I clarify anything for you?
Yes, they can ask you what your assessment was of his speed.