Why none default value?
For basically all highways in the OSM a shared use is assumed. This comes form the common traffic rules which allow shared use too. E.g. pedestrians can use all roads while walk at the border of the road. Only in uncommon cases traffic signs are set up (a motorway is uncommon). So a shared way for cyclists and pedestrians is normal.
Why is segregated=no default for all highways but not for a Shared Foot- and Cycleway? --Hb 11:43, 31 May 2015 (UTC)
- If a way is forbidden for motorvehicles (German sign 260 ), but allowed for non-motorized traffic (and perhaps motorized agricultural vehicles), the shared use by pedestrians and cyclists is the default value.
- But ways marked by blue signs for pedestrians and/or cyclists are reserved ways (DE: Sonderwege). In D, A, CH, F, each of these spaces is allowed only for the kind of traffic marked on the sign. Also roadside footways (sidewalks) and cycleways only marked by surface design are reserved spaces.
- The default value "for all modes of traffic" only exists for carriageways (with those well known exceptions in case of adjacent obligatory cycleways, bridleways etc.) and for (isolated) tracks.--Ulamm (talk) 12:48, 31 May 2015 (UTC)
JOSM rejects this
If I use the tags as decsibed here, JOSM complains "verdächtige Merkmalskombination - highway=footway zusammen mit bicycle=designated" ("suspicious combination highway=footway/bicycle=designated"). Who is right? "highway=üath" is accepted. --GerdHH (talk) 11:11, 11 June 2017 (UTC)
What about highway=footway bicycle=yes
"This key has no default value and should be tagged on all shared ways!"
Is it actually useful to tag it on highway=footway bicycle=yes? It seems that segregated=no is obvious there. See also https://josm.openstreetmap.de/ticket/20318#ticket
After all, if bicycles would have its own designated space, then it would be bicycle=designated, right?