The similarity that appears to me is that the existence of a hyperlink (the visual cue) condenses text around it into a chunked thought.

Ah, I can see that. And I agree, if used responsibly, it probably accomplishes that to some degree. Again, what Less Wrong is lacking here is good summaries that allow the single word to actually encapsulate a relevant idea. (Or, as I noted in another comment, a glossary, so people can quickly learn new terms without reading entire articles)