@evan indeed. The SocialHub is just a default discussion place and not required in the process, yet discussing there ensures it reaches a community with many devs active in AS/AP and knowledge is also conserved in one place for the longer term.
This in contrast to huge amounts of insights being passed around in toots in numerous exchanges between people.
The 3-stage Standards Process should encourage discussion on SocialHub for FEP's, just as it should encourage further follow-up towards W3C.