Its already kind of nebulous, what with MPLS no-decrement-ttl and tunneling protocols.
Add to that geo ip is often fantastically wrong. Especially if the ISP has no need for it for its own troubleshooting. They might not go out of their way to update geoip correctly, relying on the routers hostname for information.
Blowing it up to display it on a map and pretend like the data returned from traceroute is aligned with reality rubs me the wrong way.