It seems like an odd preference in the first place, though. You write "...the bullets should be hanging so they don’t disrupt the flow of the text," but isn't the point of a bullet list to disrupt the flow of text in order to focus on the individual items? Most hanging bullets I've seen have been a distraction because the content of the list is lost in the body of the text plus there's this heavy element (the bullets themselves) sticking out in the margin.

> how emphasized the bullet lists need to be

Exactly. For me, the indented list emphasizes the distinct structural entity, contrasting it against the bulk of the text. This makes lists easier to recognize (especially the short ones in narrow columns, like in your example) while previewing and skimming the reading material. You mention pattern recognition at the start of the article, and this is exactly the thing that makes pattern recognition easier, for me at least. And I would prefer “practically useful” over “typographically correct” every time :-).

>And I would prefer “practically useful” over “typographically correct” every time :-).

That is a good guideline.

Spaced paragraphs are another good example of this. Apparently they "make skilled typographers cringe" but break the text up arguably more clearly, and look fine, at least to an unsophisticated rube like me.

I use bullets intentionally to break the flow. Nowadays many readers are getting tired of too long passages, and bullet points are one way to give the text visually more structure.

Yup, that's a great point. This article is based on a chapter from my book but this is chapter 6 out of 13 already. In earlier chapters, I discuss how we need to know the content, the goals of the text and what are the user's goals (read, skim, search etc.). Of course, we can't be 100% sure on their goals but we can take an educated guess based on the content we're designing with. Decisions like these should be based on that (+ personal preference of course).