FedWiki isn’t an end-all - that’s clear. What is less clear is where it fits with respect to other software agents and environments.
What I mean is that fedwiki has constraints that define its use more tightly than the traditional wiki. The narrow column, for instance. The draggle paragraphs. The fragmenting of of paragraphs and headings that make borrowing and reorganizing so easy also make accidental separation of paragraphs from one another too easy. Paras become separate from heads. Paras become reorganized.
This is not to mention the developing style guide advice: keep paras short, confined to a single idea, place external links at the end of the para, etc. All good advice for mining and notes. Not necessarily good advice for essaying.
And the style advice is warranted, at least at first blush. As Mike C mentions, following style advice makes sharing the notes "easier" - whatever that means. Provide context - that's good advice. But contexts change when notes are moved from one space to another. That's what complicates the idea of the bounded paragraph.
FedWiki is not a publishing platform - and that might be the biggest change between FedWiki and traditional wikis. It's a distribution system, but not a publishing platform.
The question of, When do we move away from fedwiki to create other works? is addressed: when you want to publish for distribution. Move to blog.