Proposing an new speed_limit_implied=yes tag for roads with default speed limits where for some reason mapper was unable to be more specific

[Mateusz_Konieczny]

@westnordost

E.g. there is a long road, split into three sections, in first section there is an explicit sign while in the others there isn’t because that speed limit is still valid => that tag could/would be tagged on the second and third section?

I expect that such section should not be tagged as having implicit default speed limit as explicitly signed numeric speed limit still applies.

the same in case where we have speed zone areas

maybe there is a better way to solve/tag this, I am not married to this specific tag definition and name - rather I am trying to solve the problem

@westnordost

If yes, do you consider that tag to be some kind of intermediate value that should be replaced by the proper value (maxspeed=…) by another mapper - like a fixme - or a tag that also signifies that there is no sign on that section (and therefore whatever applied before applies here too) and therefore would remain forever, on very many ways?

depends on location:

in Poland it should be fixable by fairly doable survey (depending on location built-up area signs - start and end ones)

as I understand in some USA regions it can be obscure trivia which speed limit applies, and such cases would appear much rarer. There I expect it may stay effectively forever, even if in theory some more specific tagging can be invented and applied.

Once someone bothers to invent how to distinguish for example “rural winding mountain road” and “rural open mountain road”.

In other areas I expect a gradient between these cases - in some it can be expected to be tagged more specifically, in some small slivers of roads would stay marked with “weird things happen here with speed limits”.