Bullets are
supposed to break up the natural flow. That is what they are there for! If you look at nicely typeset material, the bullets are typically indented slightly rather than lined up exactly with the left margin, which gives a visual cue like the indent on the first line of a new paragraph (or a vertical space between paragraphs).
Hanging quotes fully in the margin is poor, too. The point of hanging punctuation is to optically align the margins so that they look straighter to the reader, because small glyphs like quotation marks and hyphens don't fill the space as much as typical letter forms. The idea is to avoid a distracting "bump" where the text appears to have a small indent, even though mathematically it doesn't; thus the technique complements the sort of thing you should be doing with bullets. But this is a subtle effect, and hanging punctuation fully in the margins like that certainly doesn't achieve this goal: in fact, it's probably just as bad as not hanging at all. (If you want to do it as a stylistic/aesthetic thing on block quotations or something, I'm not complaining, but this article presents it as an absolute rule for normal text.)
The whole Fibonacci/golden ratio thing is just silly, too. Who says these things have a natural elegance? Where is the research, or even the study of more than the three people in the room, to back this up?
Then there's what should have been a good point about emphasis, which completely misses the point of different typographic effects. Italics are subtle effects that show emphasis as you read without grabbing the attention, so useful for indicating things like stress or distinguishing foreign words. Heavy type, on the other hand, affects the typographic colour and draws the eye across the page. This makes it very bad for the uses of italics above (which are unhelpful out of context) but excellent for highlighting key words being defined or headings. Underlining in printed material is almost always a mistake (it distracts the eye and slows reading speed, and is unnecessary when we have proper italics available anyway) and on web pages should probably be reserved for hyperlinks since anything else clashes with user expectations.
I'm sorry, but this really isn't a guide to good typography at all, beginner or otherwise. It's just yet another list of dogmatic rules that have no sound basis, and the typography world has more than enough of those already.