diff --git a/internal/check-packet-charts.mjs b/internal/check-packet-charts.mjs
index 710172b0e..9d268f3dd 100644
--- a/internal/check-packet-charts.mjs
+++ b/internal/check-packet-charts.mjs
@@ -12,7 +12,7 @@ import { readFileSync } from 'node:fs'
 import { fileURLToPath } from 'node:url'
 import { dirname, join } from 'node:path'
 import {
-  assertNested, assertOnePublisher, fractionFromPercent, overlayPlacement, scatterCells, scatterSpread, overlayCaption, cellCount, shareCells, peoplePerCell, shareOfLists,
+  assertNested, assertOnePublisher, bracketSpan, fractionFromPercent, overlayPlacement, scatterCells, scatterSpread, overlayCaption, cellCount, shareCells, peoplePerCell, shareOfLists,
 } from '../library/components/charts/packetCharts.js'
 
 const DATA = join(dirname(fileURLToPath(import.meta.url)), '..', 'data', 'people-groups')
@@ -66,6 +66,25 @@ ok(cap.parts.map((p) => `${p.stepId}:${p.groups}`).join(' ') === 'unreached:2082
   'as inkable parts in step order — an unexplained band on paper tells a reader nothing')
 ok(cap.isSlice === false, 'and the caption says it is not a slice, so the component need not decide that itself')
 
+// ── an overlay that cannot be placed must not be DRAWN (found by reading the template) ──────────
+// ★ THIS SHIPPED IN L61 AND I CAUGHT IT BY READING, NOT BY A TEST. The component computed its
+// bracket with Math.min(...idx) / Math.max(...idx) over the steps an overlay touches. On an EMPTY
+// list those return Infinity and -Infinity, so the bracket rendered at y=Infinity with height
+// -Infinity — an invalid rect that SVG discards without a word. The overlay vanished and took its
+// groups with it: no error, no gap, just a chart missing a band nobody knew to look for.
+// The input is easy to get wrong because `within` is the unusual half of the API — an overlay
+// written as { id, label, groups } looks complete and is unplaceable.
+ok(bracketSpan(DOXA, STEPS) !== null, 'a well-formed overlay places')
+ok(bracketSpan({ id: 'list', groups: 100 }, STEPS) === null,
+  'an overlay with NO within returns null rather than a bracket at Infinity')
+ok(bracketSpan({ id: 'list', groups: 100, within: { typo: 50 } }, STEPS) === null,
+  'and so does one whose within names a step that does not exist — a typo cannot silently delete a band')
+ok(bracketSpan({ id: 'list', groups: 100, within: {} }, STEPS) === null, 'an empty within too')
+// NEG CONTROL: the old expression really did produce the broken geometry, so this is not theory.
+const emptyIdx = []
+ok(Math.min(...emptyIdx) === Infinity && Math.max(...emptyIdx) === -Infinity,
+  'NEG CONTROL: Math.min/max of an empty span ARE Infinity/-Infinity, which is what drew the invisible rect')
+
 // ── the calendars ───────────────────────────────────────────────────────────────────────────────
 ok(cellCount(100, 52) === 5200, 'a 100-year life in weeks is 5,200 cells')
 const share = readJson('christian-share.json')
diff --git a/library/components/charts/VisionFunnel.vue b/library/components/charts/VisionFunnel.vue
index 7e1c39192..34ad5a807 100644
--- a/library/components/charts/VisionFunnel.vue
+++ b/library/components/charts/VisionFunnel.vue
@@ -21,7 +21,7 @@
  * text-align: start) rather than left/right.
  */
 import { computed } from 'vue'
-import { assertNested, assertOnePublisher, overlayCaption, shareOfLists } from './packetCharts.js'
+import { assertNested, assertOnePublisher, bracketSpan, overlayCaption, shareOfLists } from './packetCharts.js'
 
 const props = defineProps({
   /** Strictly nested, outermost first: [{ id, label, groups, population, source }] */
@@ -68,19 +68,23 @@ const height = computed(() => PAD * 2 + props.steps.length * STEP_H)
  * An overlay's bracket spans the steps it reaches into. It is positioned BESIDE the funnel, so it
  * can cross two steps without asserting that either contains it.
  */
-const brackets = computed(() => props.overlays.map((o) => {
-  const cap = overlayCaption(o, props.steps)
-  const idx = cap.parts.map((p) => props.steps.findIndex((s) => s.id === p.stepId)).filter((i) => i >= 0)
-  const from = Math.min(...idx), to = Math.max(...idx)
-  return {
-    ...cap,
-    label: o.label,
-    population: o.population,
-    y: PAD + from * STEP_H,
-    h: (to - from + 1) * STEP_H,
-    isHighlight: o.id === props.highlight,
-  }
-}))
+const placed = computed(() => props.overlays.map((o) => ({ o, span: bracketSpan(o, props.steps) })))
+
+const brackets = computed(() => placed.value.filter((x) => x.span).map(({ o, span }) => ({
+  ...overlayCaption(o, props.steps),
+  label: o.label,
+  population: o.population,
+  y: PAD + span.from * STEP_H,
+  h: (span.to - span.from + 1) * STEP_H,
+  isHighlight: o.id === props.highlight,
+})))
+
+/**
+ * Overlays we cannot place. Named in ink rather than dropped: an overlay whose `within` is missing
+ * or names an unknown step has no known relationship to the steps, and silently omitting it loses
+ * its groups from the page with nothing to say so.
+ */
+const unplaced = computed(() => placed.value.filter((x) => !x.span).map(({ o }) => o))
 
 const ofKText = computed(() => {
   const k = props.ofK ? shareOfLists(props.ofK.index, props.ofK.total) : null
@@ -115,6 +119,9 @@ const ofKText = computed(() => {
           <span v-if="!b.isSlice && labels.notASlice" class="vf__caveat"> {{ labels.notASlice }}</span>
         </li>
       </ul>
+      <p v-for="o in unplaced" :key="o.id" class="vf__unplaced" role="alert">
+        {{ o.label || o.id }} — {{ o.groups }}{{ labels.unplaced ? ' · ' + labels.unplaced : ' · cannot be placed: no `within` naming a step in this funnel' }}
+      </p>
       <p v-if="ofKText" class="vf__ofk">{{ labels.ofK || '' }} {{ ofKText.index }} / {{ ofKText.total }} · {{ ofKText.percent }}%</p>
     </template>
   </figure>
@@ -132,6 +139,7 @@ const ofKText = computed(() => {
 .vf__step, .vf__overlay, .vf__ofk { font: 400 12px Georgia, serif; margin-top: 4px; text-align: start; }
 .vf__overlay--hi { font-weight: 700; }
 .vf__caveat { opacity: 0.8; }
+.vf__unplaced { font: 700 12px Georgia, serif; color: #8a1c1c; margin-top: 4px; text-align: start; }
 .vf__error { font: 700 13px Georgia, serif; color: #8a1c1c; border: 2px solid #8a1c1c; padding: 8px; }
 @media print { .vf__band, .vf__bracket { print-color-adjust: exact; -webkit-print-color-adjust: exact; } }
 </style>
diff --git a/library/components/charts/packetCharts.js b/library/components/charts/packetCharts.js
index 5afa502da..88944cf71 100644
--- a/library/components/charts/packetCharts.js
+++ b/library/components/charts/packetCharts.js
@@ -116,6 +116,29 @@ export function overlayCaption(overlay, steps) {
   }
 }
 
+/**
+ * Where an overlay's bracket starts and ends, or null when it cannot be placed at all.
+ *
+ * ★ null IS THE POINT. An overlay whose `within` is missing, empty, or names a step that does not
+ * exist has no known relationship to the funnel — and "unknown" must never be drawn, because a
+ * drawn bracket asserts a span. This lived inline in the component as
+ * `Math.min(...idx)` / `Math.max(...idx)`, which on an empty list returns Infinity and -Infinity,
+ * so the bracket rendered at y=Infinity with height -Infinity: an invalid rect that SVG discards
+ * without complaint. The overlay simply vanished, and its groups vanished with it.
+ *
+ * It is an easy input to get wrong, too: `within` is the unusual half of the API, and an overlay
+ * written as { id, label, groups } alone looks complete. So the caller gets null and the component
+ * says so in ink rather than drawing nothing and calling it a chart.
+ */
+export function bracketSpan(overlay, steps) {
+  const cap = overlayCaption(overlay, steps)
+  const idx = cap.parts
+    .map((part) => (steps || []).findIndex((s) => s.id === part.stepId))
+    .filter((i) => i >= 0)
+  if (!idx.length) return null
+  return { from: Math.min(...idx), to: Math.max(...idx) }
+}
+
 /** Cells in a calendar grid. 100 years x 52 weeks is 5,200. */
 export function cellCount(rows, columns) {
   return (Number(rows) || 0) * (Number(columns) || 0)