A long-SHORT, SINGLE-INSTRUMENT, single-venue trend-following strategy on ETHUSD_PERP.BINANCE_CM (COIN-M inverse perpetual, ETH-margined, MARGIN account, ~0.06% RT taker) using 4-HOUR OHLCV bars only (NO funding/OI/liquidation/IV supplementary data, NO second instrument, NO CASH-spot engine path). The strategy runs a simple two-EMA crossover for direction and an ATR trailing stop for exits — three parameters total (fast EMA, slow EMA, ATR multiple) to stay well clear of the overfit signature that killed the multi-parameter breakout/veto strategies this session. The differentiating edge is structural, not parametric: on inverse (coin-margined) contracts a fixed coin-denominated position gives convex USD exposure — exposure grows as the trade moves in your favor and shrinks as it moves against you — a free long-gamma-like payoff that amplifies winning trends and de-risks losers. Trend-following is the natural harvester of that convexity, and it is entirely absent on linear USD-M contracts, so this is a fresh expression rather than a re-run of the USD-M single-asset TSM family already in the portfolio. Risk profile: risk 1.5% of equity per trade (sized in ETH-margin terms); position re-sized on each entry to keep risk-to-stop constant; ATR(14)-based trailing stop at 3.0x ATR; no fixed take-profit (let convexity run the trend, trail it out); single position at a time; max single-position notional 25% of equity; leverage 2x (within COIN-M cap). Low turnover (4H EMA crossover holds multi-day trends) keeps fee drag trivial against the 0.06% RT cost.