A short-horizon, long-short trend/breakout strategy on 15-minute bars across the three most liquid Binance USD-M majors (BTC, ETH, SOL), designed to fill the under-represented short_1m_15m horizon bucket WITHOUT falling into the fee-domination trap that kills naive intraday bar strategies. The core idea: trade only GENUINE volatility expansions — bars that break the recent intraday range by a LARGE multiple of ATR — so every entry follows a move that already dwarfs the ~0.10% round-trip fee, and the strict filter keeps trade count low (a few per asset per week, not hundreds per day). This is the same validated trend/breakout primitive as the factory's promoted edge (the Sharpe-1.48 trend basket), just at an intraday cadence to capture the short-horizon continuation that daily strategies miss. It is deliberately on the only reliably-backtestable surface — Binance USD-M majors, pure OHLCV, full history — avoiding every infrastructure block hit this session (Deribit options, COIN-M inverse sizing, Hyperliquid alt bars, liquidations live-WS-only, multi-leg funding primary-only) and every refuted class (no funding, no basis, no ratio MR, no options). Long-short (per-asset directional breakouts) improves the portfolio's 87%-long skew; the ATR-gated large-move requirement is the explicit fee-domination defense; few parameters resist overfitting.