Kevin:
Great question and sharp insight...
The answer to this question in not as simple as it could be but it is not that involved either. I will not attempt to answer this question in a general sense, but only as it applies to the current 'north-of' natural language relationship specific case.
First lets establish a context in which we may answer the question. Two basic structuring situations will be addressed in this context:
Case 1) North-of relationship: only one city at each latitude
Case 2) North-of relationship: more than one city at each latitude
In Case 1, the asymmetric logical property is used to order the cities. The cities are not ordered directly, however. The equivalence classes are ordered and each equivalence class has only one city. In this case we do not have to evaluate each city to see if it belongs in an equivalence with another city, it does not, by definition.
Therefore, in Case 1, the only operational function is ordering of the cities.
In Case 2, the asymmetric logical property is used to order the equivalence classes. However, there are two functions in play in Case 2. The first function is the ordering of the equivalence classes. The second function is the determination of class membership or equivalence. The ordering function requires an asymmetric logical property. The equivalence function requires a symmetric logical property.
When answering 'no' in both directions, the natural language relationship is 'equal', which has a symmetric logical property.
After the equivalence function is completed, then more empirical data is collected and the Case 2 process is continued.
These uses are standardized and documented in the associated ART form. If there are cases where the standard form needs to be adjusted, then the adjustment procedure is recorded in the standard ART form.
Please let me know if you have any further questions, comments and/or concerns,
Joe