This is fascinating Chris, thanks for sharing. This functionality reminds me a bit of the GNU Social plug-in for WordPress, which was created to allow comments on a WP blog to appear both on the blog, and in the poster’s timeline on the GNU Social host they microblog on.
I’m not sure if this WP-plugin is being actively used any more. If it is, it will soon need a major rebuild to use the ActivityPub standard that will effectively replace OStatus over the next year or two, as the flagship standard for decentralized microblogging. It would then become compatible not just with GNU Social, but with all the federated social network apps collectively known as the “fediverse” (except for Diaspora).
Further research shows there’s already more actively developed OStatus plug-in for WordPress that supports both GNU Social and Mastodon, and a bunch of other WP-plugins for Mastodon, which between them provide some or all of the required functions for AP support. There’s also the WordPress plug-in for the Charitable platform, who are now promoting their AP support. I presume all of this work depends on the WP-plugin for ActivityStreams, one of the protocols used in both OStatus and ActivityPub.
BTW Somewhat ironic that were are both advocates of a decentralized web, and critics of the corporate datafarms (“someone else’s intranet” as you put it), yet here we are making contact on a corporate datafarm, created by a founder of one of the current titans of datafarming 😉 I’m curious, do you mirror your writing here to increase discoverability, or do you write separate streams of content for your WP site and for Medium?