BTC 4H Prior-24h High/Low Failed-Breakout Rejection Long-Short (BINANCE USD-M Futures, 4H, OHLCV-Only, Price-Level Mechanism)

Single-instrument long-short failed-breakout-reversal strategy on BTCUSDT.BINANCE that fires when price tests an established 24-hour pivot level but fails to break through, indicating that the level holds as resistance/support and a reversion is likely. Mechanism reads PRICE LEVELS (prior 24h high = PDH, prior 24h low = PDL) and intra-bar excursion vs close: when the current 4H bar's HIGH pierces PDH by more than a threshold (failed breakout attempt) BUT the close is back below PDH by more than a threshold (rejection confirmed), enter SHORT — the bulls tested and failed. Symmetric LONG entry when the bar's LOW pierces PDL but close is back above PDL. This is the mechanical COUNTERPART to the portfolio's landed breakout family (BtcFourHourVolumeBreakoutLong, MultiTimeframeBreakoutETHSOLLong, etc.): those strategies fire when a breakout SUCCEEDS; this strategy fires when a breakout FAILS — they cannot both signal on the same bar, so they're complementary rather than redundant. ZERO SUPPLEMENTARY DATA, ZERO EXTRA INSTRUMENTS, ZERO EXTRA BAR TYPES — purely BTCUSDT.BINANCE-4-HOUR OHLCV on the proven data path used by all my five currently-in-pipeline BTC 4H hypotheses (BtcAggressorFlowProxy, BtcAsianSessionUSReversal, BtcConsecutiveDirectionalStreak, BtcOpenInterestSurgePriceExtension, BtcRangeExpansionExtremeCloseRejection). Fills three under-represented portfolio buckets that NONE of my prior hypotheses addressed: (1) long-short direction (currently 9.7% vs ≤55% long-only ceiling — most-violated quota); (2) PRICE-LEVEL / failed-breakout mechanism class (entirely absent from all 956 experiments — every existing breakout-based strategy trades successful breakouts, none trade failed ones); (3) support/resistance pivot-rejection signal type (orthogonal to taker flow, session time, bar sequence, OI positioning, range anatomy, volume breakout). Expected ~100-200 entry cycles per year × 6 years of BTC 4H data ≈ 600-1200 trades, dramatically above walk-forward sample-size floor. Mechanism is BTC-specific, structurally immune to AVAX-style cross-asset analog overfitting since no family-portability claim is made.