[Tagging] Boundary Relations. What's a subarea used for?

[moltonel 3x Combo]

On 08/01/2015, Steve Doerr <doerr.stephen at gmail.com> wrote:
> On 08/01/2015 01:21, Dave F. wrote:
>
>> Are they relevant? If so, what are they for? The wiki suggests they're
>> superseded:
>> http://wiki.openstreetmap.org/wiki/Relation:boundary#Relation_members
>>
>
> No it doesn't, it says they're 'optional, disputed, and redundant'. The
> term 'redundant' has multiple meanings, but I take it to mean 'not
> strictly necessary', 'not adding additional information', or some such.
>
> I'd say leave them unless they cause a real problem. Out of respect to
> the mappers who have gone before you, if nothing else.

On a related note, I'd love to see
http://wiki.openstreetmap.org/wiki/Relation:multilinestring in wider
use. Repeating the same 100 ways in 10 different relations is a waste
of both contributor and computer ressources.

Another related/complementary/alternative option is that big
multipolys (such as countries) use smaller multipolys (such as
regions) as their role=inner members. That's actually very close to
the subarea concept, but reusing an existing wheel. I'm not sure how
frequently that's used, and how to draw the line between that and
multilinestring.