I'm still catching up on the whole discussion, but I'd mention that WriteFreely sends out Articles by default, with a config option to send Notes instead.

I've experimented with automatically falling back to Note if a post has only one paragraph, but agreed that's not a great distinction. (And I don't think an automatic switch should be needed for a platform like ours.)

Definitely inclined to agree with @trwnh that intent makes the difference. Since WF is meant for blogging / long-form, where each Actor has a unique webpage, Article was the easy choice. The hope was that other platforms would figure out UX on the other end eventually.