yeah, when i used to live in New England, and had more time to be interested in transit, i always was peaked in how comcast would route. No matter how far south i seemed to get, i'd always need to travel to Boston's peering point first to make it to NYC, even in New Haven. If you then simply switch isps, even at same address, verizon would send you south immediately.

so theres funky overlap wherein on one isp you appear closer to city A, and on isp 2 closer to city B, but its same physical address.

Continental classification I'd think would be good as they appear to be coalesced endpoints, separated by vast oceans.