XRP Dual-Signal Momentum Confluence, Long-Short (Single-Instrument XRPUSDT.BINANCE Perp, 4H Primary Momentum + 1D Trend Confirm, Flat on Disagreement, ATR-Trailing, DELIBERATELY 2-Parameter to Resist Overfit)

A LONG-SHORT, single-instrument, pure-OHLCV momentum-confluence strategy on XRPUSDT.BINANCE USD-M perpetual — the ONE mechanism family with demonstrated positive edge in this factory (the paper-stage BTC dual-timeframe momentum confluence, Sharpe ~1.99). Rather than churn another generic single-name signal (this session has now CONFIRMED that Donchian breakout and range mean-reversion produce negative per-trade expectancy on measurable samples — they have no real edge), and rather than a banned majors cross-sectional rotation (L32), this attacks the specific reason the prior confluence PORTS died: they died on OVERFIT (3-parameter fits, PBO>0.5, holdout collapse). The fix is a DELIBERATELY 2-PARAMETER construction (one momentum lookback + one ATR-trail multiple) — a smaller fitting surface that is structurally harder to overfit in walk-forward. The instrument choice is a genuine thesis, not a blind port: XRP has a distinctive fat-tailed return profile — long dormant ranges punctuated by violent multi-day vertical repricings — which is precisely the regime where a confluence filter that sits FLAT unless fast and slow momentum agree, then rides the explosive leg with a trailing stop, extracts its edge. It fills the under-target LONG-SHORT bucket (13.4% vs an 86%-long-only book) and adds SYMBOL diversity (XRP is under-tried as a focused single name and has low correlation to the BTC/ETH trend cluster). It sits in the proven fee-viable / measurable-sample zone: 4H swings holding 1-4 days capture 3-10%+ XRP legs (far above the ~0.10% fee), and ~120-200 signals over multi-year Binance history give the analyst a robust, measurable sample — avoiding both the fee_edge death of intraday systems and the unmeasurable-sample death of low-frequency gates. Simple pure-OHLCV single-instrument standard indicators → survives the developer without swaps/timeouts.