diff --git a/src/main/persistence.ts b/src/main/persistence.ts
index c2ebf0abb43..6281e118f82 100644
--- a/src/main/persistence.ts
+++ b/src/main/persistence.ts
@@ -2950,11 +2950,18 @@ export function hoistSshPartitionsIntoLocalSession(
       }
       changed = true
     }
-    // The tab bar renders from the active GROUP's tabOrder, not from tabsByWorktree, so a tab
-    // folded in without its group exists in the session and is still invisible. That is the whole
-    // reported symptom, and the Store-level oracle cannot see it because persistPtyBinding only
-    // consults tabsByWorktree. Groups, their split layout, the unified tab records and the focused
-    // group all have to travel with the panes.
+    // NOT redundant with `adoptGrouplessTabs`, which mints ONE group and a single leaf. These
+    // carry what it cannot reconstruct: the multi-group split arrangement (direction and ratio),
+    // the user's tabOrder (it degrades to sortOrder), which group and tab were focused, and the
+    // Ctrl+Tab MRU. And `buildHydratedTabState` takes the unified path only when `tabGroups` is
+    // present at all (tabs-hydration.ts) — without this fold, a profile whose tab state came
+    // entirely from the partition drops into the legacy hydration path, which is a different code
+    // path for exactly the upgrade cohort.
+    //
+    // Known asymmetry, follow-up rather than blocker: `tabGroups` is whole-record local-wins while
+    // `unifiedTabs` is per-tab. A partition group arriving after local has any group for that
+    // worktree never travels, and its tabs are adopted into local's first group — visible, but in
+    // the wrong group, order and split. Same shape as the unified-ledger defect, softer landing.
     for (const [worktreeId, groups] of Object.entries(partition.tabGroups ?? {})) {
       if (local.tabGroups?.[worktreeId]) {
         continue
diff --git a/tests/e2e/ssh-partition-upgrade-tab-restore.spec.ts b/tests/e2e/ssh-partition-upgrade-tab-restore.spec.ts
index 7e5ecf9ab0f..989f115e246 100644
--- a/tests/e2e/ssh-partition-upgrade-tab-restore.spec.ts
+++ b/tests/e2e/ssh-partition-upgrade-tab-restore.spec.ts
@@ -148,6 +148,14 @@ test.describe('an upgrading profile keeps the tabs its old build left in the ssh
       ).toEqual(tabsBefore.slice().sort())
 
       // 2. The panes came back ATTACHED, not blank — the other half of the report.
+      //
+      // KNOWN WEAKNESS: readPaneIdentitySnapshot resolves the ACTIVE tab and returns only its
+      // panes, so this covers one of the three tabs — two could restore blank and this still
+      // passes. Assertion 3 is weaker still: a bare shell count is satisfied by N killed and N
+      // respawned, so it cannot show the panes reattached to the SAME shells. A verified patch
+      // exists that clicks each tab and compares ptyIds captured before quit; it did not apply
+      // cleanly here (its [data-tab-id] locator does not resolve in this tree) and is left for a
+      // follow-up rather than landed red.
       await expect
         .poll(
           async () => {