[Tagging] maxspeed=signals

[Martin Vonwald]

2012/6/26 Philip Barnes <phil at trigpoint.me.uk>:
> Do we need a separate tag such as limit = variable, maxspeed = 70mph. At
> present there is a note about active traffic management but I assume is
> ignored by routers.

Actually I think we do need a different tagging and also some
different interpretation of the maxspeed tag itself:
* First of all the maxspeed key should always contain the maximum
allowed speed - even if it may vary. And it should always be a number.
The only exception should be "no" for the cases where there is no
legal speed limit. So IMO "signals" should be deprecated (currently
used about 4000 times -> 0.18%)
* A different tag should be used if the speed limit is somehow
managed, maybe maxspeed:managed=yes or something similar.

Why do I think that maxspeed=signals is a bad idea? Because it doesn't
carry a lot of useful information. The speed limit is especially
important to routing applications. For such an application
maxspeed=signals is no information at all and it might fall back to
the country-specific default limit - and this may (and will quite
often) be wrong.

Martin