[velcrovan]

That's why an address consists of more than a street name and a number. It includes town, province/state, postal code, and country. When given two actual complete addresses, it is indeed possible to infer relative distance with reasonable accuracy, exceptions notwithstanding. (And I live near St Paul Minnesota!)

Even granting that your “nasty exceptions” comprise fully half of all complete addresses, that would simply mean that a normal addressing scheme is better than W3W 50% of the time and no worse in all other cases.