Thank you for pointing me on your proposal on the forum on that matter.
I think that I understood most of it, but probably not well enough to explain how the combination of the tags area:highway / (area+highway) make sense according to your definition in this case here. Either most people follow the addition way or they stroll around in a probably larger area. 

As discussions here are  tedious, and this is relevant for a broader audience, I will add a post in the community forum in the afternoon pointing to this case here and ask you to answer my question there.

I think that you fixed the unconnected_open_ends issues OSMI detected by adding of the noexit=yes tags, but in order to be sure we need to wait for a new run with the actualized data.