Multi-Family Strategy Bakeoff

A two-layer SEARCH → CERTIFY funnel with a mandated minimum body of work. The central rule: a verdict is FORBIDDEN from the search layer. Only walk-forward certification (walk-forward-oos) can end the campaign.

Two tools, two jobs

• SEARCH layer (cheap): backtest_portfolio, create_portfolio_variant, optimize_portfolio, systematic_sweep. It may only KILL or PROMOTE an idea into certification. It outputs "a ranked set of SEEDS" and may never issue a verdict.
• CERTIFY layer (workhorse): walk-forward sweep certification on promoted seeds. Only this layer can conclude PASS / FAIL or "no deployable winner."

systematic_sweep over the deployment × structure × DTE × delta grid is mandatory in the search layer before any neighborhood is declared dead.

The mandated minimum body

• ≥ 3 distinct mechanism families certified before any "no winner" verdict. Genuinely different mechanisms, not three tweaks of one family. Family menu (pick ≥3): (a) momentum long calls/verticals; (b) regime-switch long/flat; (c) defined-credit / short-premium (earns in flat/down tape); (d) calendar / diagonal time-spreads; (e) protective-collar or put-spread-financed longs.
• Up to 3 certification attempts per family (re-sweep from a CLEAN seed with refined gene_intents, deeper grid, or wider validation) before a family is "exhausted."
• Realistic total: ~3–9 sweep certifications, plus the incumbent certified as a seed.
• Each sweep non-trivial: ≥3 gene_intents axes × ≥3 values each (see sweep-reoptimization for the exact field mappings). A 1-axis or 2-value sweep does NOT qualify.

Per-family certification ledger (required)

Log this table in the run log — a family with no ledger row was NOT explored:

| Family | Seed id | get_sweep_surface ✓ | gene_intents axes | Study id | crossFoldRobustSelection key | Assembled book id | Per-fold OOS gate result | PROMOTE / KILL (reason) |

Per-seed certification loop

get_sweep_surface → run_walk_forward_study (preview_only first) → read aggregate.crossFoldRobustSelection → assemble the deploy-shape book → gate on the assembled object → write the ledger row. Certification floors (certification:true): participation ≥ 0.35, distinct names ≥ 9, validation return ≥ 0, validation Sortino ≥ 0.5.

Verdict-integrity rules (the campaign's central discipline)

• Zero optimizing certifications = INVALID, not "an honest no-deploy." Issuing any verdict — especially "no deployable winner" / "structural infeasibility" — without optimizing certifications having run on candidate seeds makes the campaign INVALID. (A prior run declared infeasibility having run ZERO optimizing certifications.)
• No infeasibility claim from N hand-built points — must cite systematic_sweep + the ≥3-family body and name the SINGLE binding gate per family with study-id evidence.
• One counterexample in your own data forbids a blanket infeasibility claim — localize the binding constraint, don't generalize.
• Binding-constraint attribution: every kill names the single failed gate + certified evidence. "It generally underperformed" is not a kill reason.
• One mechanism change per candidate — so a kill/promote attributes cleanly.
• Remedy-coherence: a proposed remedy must not contradict the killed candidate's measured state (don't propose "raise deployment" for a book that failed under the posture cap; don't propose "add convexity" for one that failed on drawdown).

See options-structure-rules for the affordability-ladder kill path and known losers, and lockbox-holdout for the baselines (A/B/C) and the final single-touch confirmation.