Add content backlog mined from the canon

Ranks the next six sins by working backwards from the references we
already vouch for: six of fifteen canon entries were uncited, and each
idle one points at a sin worth writing. Also records the candidates our
build-time Vega-Lite pipeline can't prove honestly yet, so we stop
rediscovering them.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ULE5RRxdQE1ebwefEd2eCM

docs/content-backlog.md

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+# Content backlog — what to write next
+
+Working document. The rule that generated this list: **every sin must be
+condemned by something already in the canon** (`src/lib/references.ts`). We
+don't invent authority, so the backlog is mined *from* the sources rather than
+brainstormed and back-filled with citations.
+
+## Canon coverage
+
+Which references are already doing work, after the first three sins:
+
+| Reference | Cited by |
+| --- | --- |
+| `callingbullshit` | truncated-y-axis |
+| `clevelandmcgill` | truncated-y-axis, pie-chart-overload |
+| `tufte` | truncated-y-axis |
+| `howchartslie` | truncated-y-axis, dual-axis-deception |
+| `datatoviz` | dual-axis-deception, pie-chart-overload |
+| `spurious` | dual-axis-deception |
+| `swd` | dual-axis-deception |
+| `fewpies` | pie-chart-overload |
+| `junkcharts` | pie-chart-overload |
+| **`munzner`** | — |
+| **`wilke`** | — |
+| **`healy`** | — |
+| **`huff`** | — |
+| **`schwabish`** | — |
+| **`ftvisvocab`** | — |
+
+Six idle references. Each is an authority we've already endorsed on the canon
+page, so a sin that leans on one is cheap to justify and strengthens the page it
+sits on. The backlog is ordered to bring them all in.
+
+## Ranked backlog
+
+### 1. The Cherry-Picked Window — *Deceptive Framing*, severity 5
+
+**Poke:** "You started the clock exactly where the story got good."
+
+The trend runs one way over five years and the other way over five months, so
+the chart shows the five months. Nothing about the chart is technically false —
+the axis starts at zero, the labels are honest — which is what makes it the
+nastiest sin on this list and a good counterweight to the three scale/type sins
+we already have.
+
+**Charts:** one series, two views. Bad = the flattering slice. Fixed = the full
+record with the slice shaded in place. Literally the same dataset filtered, so
+the "same numbers, both charts" rule holds by construction — the strongest proof
+we can build.
+
+**Citations:** `huff` (the original con), `callingbullshit`, `howchartslie`,
+`junkcharts`.
+
+### 2. Bars That Hide the Distribution — *Hiding the Data*, severity 4
+
+**Poke:** "Four bars, four averages, and no idea whether the difference is real."
+
+The bar-of-means: every group collapsed to one number, so wildly different
+distributions draw identical bars. Wilke devotes a section to exactly this and
+Healy makes the perceptual case; it's the natural home for three of our six idle
+references at once.
+
+**Charts:** bad = grouped bar of means. Fixed = strip/box plot over the same
+observations, means still marked.
+
+**Citations:** `wilke`, `healy`, `schwabish`, `datatoviz`.
+
+### 3. The Inflated Bubble — *Perceptual Traps*, severity 4
+
+**Poke:** "You doubled the number and quadrupled the ink."
+
+Scaling a circle's *radius* by the value instead of its *area* squares the
+apparent difference. This is Tufte's Lie Factor with an actual number attached,
+and it's the cleanest possible excuse to bring Munzner's channel ranking onto a
+page — the same ranking that already underwrites the pie and truncated-axis
+sins.
+
+**Charts:** bad = radius ∝ value (a `calculate` transform squaring the size
+encoding). Fixed = area ∝ value, or better, the same values as a dot plot where
+position does the work.
+
+**Citations:** `munzner`, `clevelandmcgill`, `tufte`, `howchartslie`.
+
+### 4. Alphabetical Is Not a Ranking — *Sloppy Craft*, severity 2
+
+**Poke:** "Your categories are sorted by name. Nobody wants to know which
+region starts with A."
+
+Venial, universal, and the single most useful page to fire at a colleague —
+which is the whole product thesis. Low severity is a feature: the gallery needs
+a range, and this one brings in the FT Visual Vocabulary.
+
+**Charts:** bad = categorical bars in alphabetical order. Fixed = same bars
+sorted by value.
+
+**Citations:** `schwabish`, `ftvisvocab`, `swd`, `fewpies`.
+
+### 5. The Reversed Axis — *Misleading Scales*, severity 5
+
+**Poke:** "Down means up. You flipped the axis and the trend flipped with it."
+
+The famous one. High drama, trivial to author (`scale: {reverse: true}`), and it
+slots into an existing category. Ranked below the others only because the canon
+support overlaps almost entirely with sins we've already published.
+
+**Citations:** `callingbullshit`, `howchartslie`, `junkcharts`.
+
+### 6. Squashed and Stretched — *Misleading Scales*, severity 3
+
+**Poke:** "Same data, twice as tall. Aspect ratio is not a styling choice."
+
+Cleveland's banking-to-45° argument: the identical series reads as a crisis or a
+plateau depending on the box you draw it in. Cheap to author — one dataset, two
+`width`/`height` pairs — and a rare sin where the bad chart contains no false
+statement at all.
+
+**Citations:** `clevelandmcgill`, `howchartslie`, `wilke`.
+
+## Not yet buildable
+
+Real sins, but our pipeline can't prove them honestly today. Recorded so we stop
+rediscovering them:
+
+- **3D bars / gratuitous perspective** and **chartjunk** (Tufte, Few) — Vega-Lite
+  won't render the sin, and a screenshot violates the same-pipeline rule that
+  makes the before/after credible.
+- **Counts on a choropleth instead of rates** (Cairo's set-piece) — needs
+  TopoJSON geometry and a build-time data dependency we don't have yet. Strong
+  candidate the moment we take that on.
+- **Rainbow color scales for continuous data** (Wilke, Munzner) — buildable, but
+  the fixed chart needs a sequential ramp validated on `--chart-canvas` in both
+  themes. Do the palette work first (`dataviz` skill + its validator), then
+  write it.
+
+## Conventions reminder
+
+Anything picked up from this list still follows `CLAUDE.md`: the poke names the
+general sin and never our sample's numbers, both charts share one dataset, and
+the fixed chart obeys every rule the site preaches.