Headings should step down one level at a time (h2 -> h3, not h2 -> h4). Skipped levels break the document outline that answer engines and screen readers use to understand which content belongs to which section.
Impact is importance multiplied by the confidence tier’s weight — SPECIFICATION 1.0, RESEARCH 0.7, EMERGING 0.3, EXPERIMENTAL 0.1. Two rules backed by the same class of evidence therefore always carry the same weight, which is what makes the score reproducible rather than hand-tuned.