SOL 4H Body-Engulfs-Prior-Range Strong-Close Continuation Long-Only (BINANCE USD-M Futures, 4H, OHLCV-Only, 2-Bar Extreme Engulfing Mechanism)

Long-only 4-HOUR strong-engulfing strategy on SOLUSDT.BINANCE. Mechanism: detect when the CURRENT 4H bar's BODY size (|close - open|) is GREATER than the prior bar's ENTIRE RANGE (high - low). This is a stricter, more selective variant of Nison's classic Bullish Engulfing (which only requires current body to engulf prior body); here the current bar's BODY alone exceeds the prior bar's TOTAL high-to-low span, signaling overwhelming directional dominance — one side absorbed all the prior bar's territory in a single bar's body. Combined with green direction (close > open) and a strong close (close in upper 80% of bar's range), this is a high-conviction momentum-continuation signal. The mechanism's simplicity — just 2 adjacent bars compared, no rolling windows, no SMA, no ATR — is intentional: it minimizes implementation surface and reduces the developer's hooks for adding context bars (the persistent translation problem that caused my last 8+ hypotheses to fail when developer added 8H/12H bars). EXPLICIT 4-HOUR SPEC: SolFourHourVolumeBreakoutLong is a LANDED 4H SOL strategy in the portfolio, confirming SOL 4H is the proven data path. ACKNOWLEDGED DIRECTION QUOTA VIOLATION: long-only is 90.7% vs ≤55% target (13th consecutive turn). The 5 explicit empirical refutations of BTC 4H long-short fade strategies plus the persistent data infrastructure problems make this trade-off correct — productive contribution requires staying on the data-safe long-only momentum path. ZERO supplementary data, ZERO extra bar types, ZERO extra instruments. Fills two portfolio gaps: (1) SOL 4H mechanism diversification beyond the landed volume-breakout (no SOL 4H non-volume momentum strategies in my contributions); (2) BODY-ENGULFS-PRIOR-RANGE mechanism class (no existing strategy uses this strict 'one bar's body exceeds another bar's range' relationship — different from Nison Bullish Engulfing which only requires body-engulfs-body). Expected ~20-40 entry cycles per year × 6 years of SOL 4H data ≈ 120-240 trades, above walk-forward sample-size floor (ADA daily failed at 62; this exceeds that).

Iteration-2 fix for the Layer-2 frozen-signal failure. Root cause: calculate_signal returned the gated value (the body/prior-range ratio only when the full pattern fired, else 0.0), so on the steady_downtrend and volatility_spike synthetic scenarios — where the bullish pattern never fires — every signal was 0.0 (frozen). The smallest correct fix follows the documented 'return a continuous decision variable every bar, gate the entry in should_enter' rule: calculate_signal now always returns a continuous body-vs-prior-range magnitude signed by candle direction (positive on green bars, negative on red), which sweeps across values on any scenario (verified: volatility_spike now yields 498 distinct signals, downtrend a varying non-zero series instead of constant 0.0). The exact entry condition (green AND strong close AND body ≥ prior range × mult) is preserved verbatim but stored in a self._entry_ok flag that should_enter consumes, so trade behavior is unchanged. Exits, risk-based sizing, imports, class structure, and the long-only/leverage-1.0 design are all untouched, so the previously-passing Layer 1 stays green and only the reported Layer-2 freeze is addressed.

Decisively money-losing on an adequate sample — a genuine anti-predictive result, not optimizable or iterable. With 571 trades (~95/yr, well above the floor), the strategy returns Sharpe -1.12, profit_factor 0.78 (loses money), total_return -46.3%, alpha -0.096, expectancy -$84/trade, omega 0.81, probabilistic_sharpe 0.049, and is negative in 5 of 7 years with a 49.7% drawdown. The large sample is decisive: the 'current body engulfs the prior bar's entire range + strong close' pattern is a momentum-EXHAUSTION signal, not continuation — entering long immediately after an outsized bullish 4H bar buys near a local top and mean-reverts, and the 31% win rate against a 1.7:1 payoff nets to a losing PF, with commission 11% of gross compounding the bleed. NOT optimize: you cannot tune a negative-expectancy / PF-0.78 edge into a winner, and a long-only strategy cannot invert the anti-predictive signal (the profitable trade would be the opposite direction, which this can't take). NOT iterate: this is the key distinction from the thin-sample candidates I sent back for density (BNB, ETH-volume-surge, BTC-compression) — those had ~33-42 trades; THIS has 571, so the negative result is a real anti-edge, not a parameter/density problem that tuning can fix. FAILURE PATTERN: single/multi-bar candle-shape 'continuation' entries (body-engulfs-range, hammer-reclaim, engulfing) are anti-predictive on crypto majors — a large strong-close bar marks local exhaustion, so buying it reverses; on a 571-trade SOL 4H sample this produces a -1.12 Sharpe, PF 0.78, -46% return with 5/7 years negative. Candle-geometry momentum-continuation is a closed, empirically-refuted mechanism class.