Work the five delivered sources into the pages

The source-request loop paid for itself immediately — two of the five
corrected something rather than confirming it.

The Economist piece settles V1, the riskiest live claim, but our note
had over-claimed: truncating the scale is its *first* example, not one
of "several." Note rewritten to quote her. The same article turned out
to contain a dual-axis chart she caught herself on, now cited.

Datawrapper's color-scale part 1 refuted the assumption behind a queued
sin outright: it makes no argument against rainbow scales and endorses
multi-hue sequential gradients. The rainbow entry is now marked as
having no verified source at all, rather than ample backing.

The dual-axis post independently draws the same line we drew last turn
— of four uses only the alternative-scale case survives, their example
being F against C — and led to two references worth more than the blog
post: the Isenberg et al. study that tested dual-scale charts, and Few's
article working through the cases. Both ship without full metadata
rather than guessed metadata; queued.

Pie and stacked posts gave verbatim support, plus one correction: a
100%-stacked chart has two readable baselines, not one.

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

src/content/sins/too-many-pie-slices.md

@@ -21,6 +21,8 @@ citations:
     note: "His chapter on proportions puts the same data in a pie, a stacked bar and side-by-side bars, so you can see what each one costs you."
   - key: eagereyes
     note: "Kosara has actually run the experiments, and they don't support treating the pie as broken by nature — useful if someone tells you the chart type itself is the problem."
+  - key: datawrapper
+    note: "Both halves in one place: pies are “great to show how 100% divide up into a few shares” and “work best for values around 25%, 50% or 75%” — but “work best if you only have a few values – five max.”"
   - key: showmenumbers
     note: "Few’s full design manual, for when the short broadside isn’t enough to win the argument."
 ---