Records the fuel-type-boundary canonicalisation, the goldens-caught
constraint (code 33 is also the electricity-10h tariff code), and the
deferred dual-fuel/community/fabric follow-ups.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Adds the flat-roof slice (52.1 → 53.1%) and records the unifying principle
("unknown insulation → as-built age default, not uninsulated") plus the
cross-element review confirming all element types now conform.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Adds the cavity wall-U slice to the SESSION-5 block + headline table;
records the by-age-band re-split method that surfaced the G/H spike.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
47.6% → 48.6% within 0.5; immersion code mapping corrected (1=dual,
2=single); next robust leads are under-rating flat/party-fabric scatter.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Updates the headline (45.1 → 47.6%), records the four shipped fixes + the
roof-8 false-lead closure, documents the two methods that worked
(description-vs-code audit + outlier-robust categorical sweep by net skew +
median), and lists the open robust leads (whc=903 immersion HW, cat-7 storage,
dual immersion) with the scatter buckets to avoid.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Records the session-4 audit: walls/heating/controls clean; roof_construction=8
("Pitched, insulated", no measured thickness) computing U=2.30 is CORRECT, not a
bug — confirmed by user worksheet sim-case-29 (band C → Elmhurst SAP 55 ≡ our
56.75; lodged 80 is data-fidelity artifact). Lesson: "insulated (assumed)" = the
age-band default insulation level, not "well insulated". DO NOT re-chase roof-8.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Code 3 = "(other premises below)" = above partially heated space (§3.12 →
U=0.7), confirmed 9/9 on single-BP certs (the diagnostic that dodged the
lossy-floors[] contamination). Records the 7536 re-pin and the lesson that
"irreducible residual" golden notes can mask a real mapper bug.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Record that profiler lead #1 (floor_codes=3) is not a clean single cause
(bimodal + confounded), that the paired worksheet certs confirm only
codes 1/6/7 (code 3 unmapped → needs a worksheet for 0380-2087), and that
immersion_type=2 / main_control=2107 / roof_codes=1 are scatter, not
dispatch bugs. The exposed-floor-on-flats fix (§3.12) shipped at b40e0f67.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
