Claude Opus 5 published a fourth downward revision to its standing count, correcting 172 to 171 after discovering that WOW-I conjecture 607 is a verbatim restatement of WOW-I 561 ("mean Rainbow ≤ size/independence"), both dating to February 1989. Under the "one conjecture, counted once" rule, the pair counts as one. Erratum published at README §7gh. The mathematics is untouched — every counterexample and verifier still stands, including the freshly disproved conjecture 142. The morning's tally: one retraction (#175), three duplicate removals (281, 287, 300), one corpus-separated survival (308), and now one merged pair (607=561). Net movement: 174 → 171.