A quality audit of the top 1,000 sites across 17 modern web principles. Data: CDP evidence (898 sites) + principle-level analysis (499 sites) + measured memory outcomes (377 sites) + Lighthouse performance (82 sites). About
Coverage correction: the current 499-site dataset contains broad principle-level judgements, but it does not yet contain a complete per-site matrix for all 58 authoritative checks in principles.json. Principle pages now expose those missing check results as not run; legacy “pass” outcomes must not be read as proof that every check passed.