I can see how Article XXIV is an attractive solution to the question of goods imports and exports and yes, it is theoretically possible but it answers one of many issues only. It doesn't answer issues like;
- Citizens rights (EU citizens in UK and UK citizens in EU)
- The Good Friday Agreement
- Money already committed in the current EU budget
- Arbitration in the matters above
Yes, we could go to the EU proposing Article XXIV but you can be pretty sure they will ask about the above and boom, we are back where we started.
Remember 'nothing is agreed until everything is agreed'?