I anticipated that challenge, and I anticipated that sentence. Let us read the sentence:
Will it be reciprocal, or not? If it is not reciprocal, it will be unlawful; that is the difficulty. If it is intended to be reciprocal, what is the point of the sentence reassuring the EU that
“the UK is not proposing that the EU applies the UK’s tariffs and trade policy at its border for goods intended for the UK”?
Whatever the arrangement is, we know one thing about it: it will not involve the EU applying UK tariffs and trade policy at its border. Otherwise, what is the point of that qualification?