I tested 42 trading rules on 14 metals markets. Not one made money.
Copper, aluminium, steel, iron ore, platinum, palladium, plus the miners' ETFs. Trend rules, breakout rules, long-only rules. All with real costs.
Result: no rule was positive after costs. Copper lost even before costs.
The plot twist: a few "winners" looked amazing at first. Then I checked the data. Those markets had stale prices, the same open/high/low/close on 62-93% of days. The bot was "trading" a price that wasn't moving.
And the kicker: simply buying and holding the miners beat every single rule (XME +198%, COPX +149% over 2021-26).
Lessons: 1. Check your data before you trust your results. 2. Sometimes the boring option wins.
Have you ever had a backtest that was too good to be true?