Tobi - That blog post 3 is very helpful. It shows that Denny and I think alike and agree on everything. :-) His dislike for strong classification.
Which is part of my basis, to allow weak relations much more. And use them. But how to allow them, and I think the only way is through properties based on the Data Model currently.
There are many ways, and SKOS is one way to allow expressing weak relations and we already have some good support with existing properties like P4390 mapping relation type
and a host of others.
Denny and I also fear the same things, like not having a flexible enough system to describe our complex world that doesn't always fit into strict rules. Which is kinda why I've always likedhttps://www.w3.org/TR/skos-primer/#secassociative
because of it's non-transitivity which allows much flexibility and as he and I would say... avoid "Barbara". :-)
Sorry for all the SKOS links but semantic relations helps to describe human knowledge. How a system represents or portrays semantic relations is where choices are made or have been made. And I think the right choices were definitely made.
Overlaying SKOS and the Wikidata properties that sprinkle it into the data model is useful, but I've always been kind of reluctant to do that...probably for the same reasons Denny might give? Choices between allowing "semantic accuracy" versus "semantic flexibility". But I think systems like SKOS provide both. Perhaps it could be argued that OWL provides much less. :-) Still all KOSs provide great use when they fit well. How they can fit over Wikidata, as I said, is probably only through properties at this late stage of design and that's fine with me!
Still, my main focus is and always will be trying to add human knowledge about concept relations into Wikidata to help machines, to help us. (the "edges" that humans quickly can deduce in seconds, but still to this day can sometimes take machines days or weeks to figure out).
My usage and help to Abstract Wikipedia and Wikidata later on will primarily be around the mapping of relations ... where a lot of the possibilities have already been described years and years ago at the very bottom of this long page:
inter-KOS mapping relationships <--
very last row, 3rd columnhttps://www.w3.org/TR/skos-primer/#seccorrespondencesISO
Denny - were you part of or lightly influenced by
through Germany ISO DIN or not .. that also would be good to know.