[OSM-talk] Oxford High Street classification (Was: Bus sluice/gate)

[Gervase Markham]

Stephen Gower wrote:
>   There was still debate as to which bits of the A420 through Oxford
>   are not primary, and if it's not primary what is it exactly.  On
>   the former, I'd say the primary road network should not just drop
>   out (a primary dead-end, as it were) and therefore the non-primary
>   bit of the A420 is from its junction with the A4144 (at the end of
>   Thames Street) to the junction with the A4158 (Magdalen Roundabout,
>   aka The Plain).  As to which classification the highway= key should
>   have, I'd say the High is less important (from both mapping and
>   routing aspects) than its effective bypass (Longwall Street - Parks
>   Road) which has been marked as Secondary, but more important than
>   the unclassified roads coming off of it - therefore Tertiary is my
>   conclusion.

That sounds like a great answer to the question "what should a routing 
algorithm do with this situation". But the open question is, should 
highway tags be defined for the benefit of routing algorithms and/or map 
rendering (one possible view) or should they be defined according to 
legal classifications, and additional auxiliary clarification tags used 
in the occasional situation where the legal classification would mislead 
rendering/routing software.

Granted, I'm new to OSM, but I'd argue for the latter.

Gerv