Add Skyhook (SKH01_V2_DD) as a portfolio sleeve. Effective weight 25%: the three
existing sleeves scaled into the remaining 0.75 keeping their 55:25:20 ratio
(TP01 41.25% / XS01 18.75% / VRP01 15% / SKH01 25%).
_skyhook_returns(): 50/50 BTC+ETH daily series of the dual-TF regime+breakout engine
(causal, net 0.10% RT), same convention as the marginal lens.
Portfolio impact (run_portfolio.py), 3-sleeve -> 4-sleeve:
FULL Sharpe 1.68 -> 2.13 (+0.45), FULL maxDD 14.3% -> 7.8% (halved)
HOLD-OUT Sharpe 1.63 -> 2.30 (+0.67), HOLD-OUT maxDD ~3.5% (flat)
Positive every year 2019-26 (annual DD <=7.8%) vs buy&hold 50/50 FULL Sh 0.93 / DD 76%.
Skyhook is quasi-orthogonal (corr ~0.09 to TP01) so it lifts Sharpe AND cuts DD.
Research portfolio (fixed weights, no real rebalancing cost at $600; Skyhook daily
Sharpe is the step-marked lens convention) -> forward-monitor, not deploy.
Tests: 25 pass (skyhook 8 + portfolio 7 + vrp 4 + trend 6). Diary + CLAUDE.md updated.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Second agent wave (skyhook-improve-v2, 14 DD-reduction families, each adversarially
verified by 2 skeptics) beats the prior winner on the only unmet goal (DD<30%).
Winner = ASYM_LS -> promoted to engine as SKH01_V2_DD:
same signal (ptn_n=45, vola[35,95], vol_lo=0, exit-bars 24/16) but exits switched
from ATR to FIXED-PCT ASYMMETRIC — long sl4%/tp10%, short sl2%(tighter)/tp8%.
The tight short %-SL caps the per-trade loss that forms the maxDD in vol spikes.
Verified (sk.study, independent re-run): standalone maxDD BTC 21.4% / ETH 27.4% (<30%),
minFull +0.99, minHold +1.26, causality 0/400 both assets, fee-surviving to 0.40%RT,
marginal vs TP01 ADDS (corr 0.09, in-sample edge, robust_oos, multicut, clean-year +0.57),
blend 0.75*TP01+0.25*SKH uplift_hold +0.87; blend 50/50 full 1.84/hold 1.59/DD 10.7%.
Plateau (not knife-edge); both skeptics holds_up=high, killer=null.
Engine: per-direction short exit overrides (exit_mode_short/sl_*_short/tp_*_short),
backward-compatible (None -> symmetric, V1/intermediate-winner unchanged). +3 tests (8/8 pass).
Lessons: DD is cut by changing the exit MECHANISM (%-SL, L/S asymmetry, ensembles), NOT by
entry-only kill-switch / vol-target / cadence. PATTERN_CONF killed as overfit (knife-edge).
PCTL_DD unverified (rate-limit) and ENS_PARAM/TPSL_DD recency/hedge-loaded -> forward-monitor.
NOT yet wired to live sleeves: re-verify blend@0.25 + causality on execution code before deploy.
Includes both waves' research scripts (runs/SKH_* wave 1, runs/SKH2_* wave 2).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Adriano Dal Pastro