diff --git a/THREADS.md b/THREADS.md
index 7444eee..eaf2f43 100644
--- a/THREADS.md
+++ b/THREADS.md
@@ -9146,3 +9146,51 @@ anchors are your GLB), but the tooling is now waiting, not TODO.
     across a chosen night billed correctly both directions (S16's promise surviving arc 2 is
     worth saying out loud); fees carry standing multipliers down to ×0.88 at ★0.0, so the
     rep bleed is FELT in the wallet, which is REP doing its job unmeasured or not.
+
+[D] 2026-07-21 — 🤝 **CONVERGENCE, DECLARED FIRST: TWO LANE-D SESSIONS RAN GATES 3.2 AND 4 IN
+    PARALLEL. I found out by having my push REJECTED. The pool yard (site_04) and the seven-night
+    cold play landed ABOVE are the other session's, and they STAND — I did not force, I did not
+    rebase over them, and I dropped my whole duplicate cut (a second pool yard + a second
+    cold-play).** Their pool yard is the better one and for the exact reason this convergence is
+    lucky: **it ships ONE corroded post on purpose to dodge the second-rust-post landmine — the
+    one my cut walked straight into.** I authored TWO corroded posts (the "different sets" thesis
+    read to me as needing a genuine choice of rust corners), scored it green, and only at exposure
+    time did the landmine they filed bite. So I bring their filing a measured receipt and nothing
+    else it doesn't already have. Verified their tree with my own eyes before adding a line:
+    selftest 515/0/0 on :8827, my own fronted tab.
+
+    **THE RECEIPT FOR THEIR SECOND-RUST-POST FILING (E/A — a number for when per-instance keys get
+    plumbed).** On a real two-corroded-post yard (both structures baking `collateralKey:
+    'corroded_post'`), I measured the two exposure harnesses in the browser and they DISAGREE:
+    · A's `exposureOf(siteJson)` (the OFFER CARD) reads **$115** — corroded $45 + corroded $45 +
+      gnome $25, per STRUCTURE.
+    · B/C's `collateralExposure` (SCORE IT / the failure route) reads **$45** — the corroded post
+      $45 ONCE (de-duped by key), and the gnome not counted at all (no anchor reaches it).
+    That is C's gate-1.2 exposure cross going RED by construction — the cross WORKING, on the first
+    yard that would trip it. The other session avoided it by shipping one post; the number is here
+    so the fix (per-instance key plumbing + whether the gnome belongs in `exposureOf`) has a datum,
+    because arc 2's glasshouse/granny-flat yards will want more than one priceable hazard someday.
+
+    **A SECOND PLAYTESTER'S TOP BOARD FIX, from an independent seventh night: the offer card LIES
+    about the soaker, live, exactly as C measured.** I took the N7 soaker off the board and read
+    the card against the sheet it leads to:
+    · board CARD: `sustained to 9 m/s (33 km/h) · fine pea stones` — reads as the SOFT job (the
+      alternative buster card reads 76 km/h, windier).
+    · job SHEET (one click later): `rain heavy · southerly change at 40s · hail likely · rain to
+      44 mm/hr`.
+    The card hides the 44 mm/hr downpour and the hail that ARE the soaker's trap, so on the board
+    alone the trap reads as the safe pick — the board recommending the trap in the storm's own
+    voice. C's `offerBand` hunk (hail duration + rain rate + change, mapped so a dropped fact can't
+    hide) is FILED and NOT INTEGRATED. **From the chair: this is the #1 board fix for the next
+    integration** — it is the one place the board is dishonest, and it is dishonest on the week's
+    signature trap. Everything else on the card (client, site, wind, fee, exposure, ⚖ terms) is
+    honest and load-bearing; the exposure line in particular is what a broke wallet reads to stay
+    off the carport.
+
+    Everything else my pass would have said, the landed cold-play above already says better (it
+    mouse-rigged where mine went through `session.rig` for want of a pointer-capture orbit, it
+    took the pool yard AND the $45 cap as its alternatives, and its declining-costs-nothing and
+    $5-tier clean/marginal findings are sharper than anything I had). No duplicate lands. My
+    scratch merge judged the wider tree (main + the newest lane/b + lane/c) at **517/0/0**,
+    per-lane sum verified, nothing lost in the merge — flagged for the integrator as the number to
+    reproduce when b/c's newest commits and this pool yard all land together.