impossible to fulfill unless the EU were to rewrite all their treaties with respect to the operation of the single market and customs union in its dealings with third countries
As long as the EU have 'special relationships' with Norway & Switzerland they do not have a single method of dealing with non-EU countries. So expecting to deal along similar lines was not asking for something 'impossible'

but effeminately for us mere mortals.
Sorry, I cannot understand your intended meaning.