Opening paragraph after the first heading on the page. The first heading has nothing above it, so it is exempt from the rhythm comparison entirely.
A closing paragraph of the previous block of content, sitting directly above the crowded heading with no gap at all between them.
The content this heading introduces sits forty pixels away while the previous block touches the heading, so the heading reads as a caption for the text above.
Another closing paragraph of a previous content block, again flush against the heading that follows it in the document flow.
Second crowded case. Two or more headings must violate the principle before the rule fires, because a single occurrence is treated as noise.
A third closing paragraph that the next heading will visually attach to, which is exactly the inversion this rule measures.
Third crowded case, this time an h3, to confirm the rule reads h2 through h4.
Sixty-four pixels above and sixteen below. The heading clearly binds to this paragraph, which is the healthy shape.
Twenty pixels above and twenty-four below. Ambiguous rather than inverted, so the rule leaves it alone.
Chapter Four
The tiny label above belongs to the heading cluster. Space is measured from the top of the cluster, where seventy-two pixels separate it from this text.
A heading inside a small card. The card boundary provides the separation, so the rule exempts headings inside panels shorter than two hundred pixels.
This heading is the first content inside a section that draws its own background, so the band edge is the separator above it.