experiment: reduce initial observation input

docs/design-evolution-log.md

@@ -321,9 +321,57 @@ Questions
 - Are we approaching a professional investigation environment?
 
 Status:
-Experimental.
+Closed.
 
-No conclusions.
+## Result
+
+Partially confirmed.
+
+## What did we learn?
+
+- Stronger visual hierarchy can direct attention without rearranging the interface.
+- The facilitator briefing became easier to distinguish.
+- Colour and tint improved separation only modestly.
+- Meaning must not depend on colour.
+- Areas and intent should remain distinguishable through structure, spacing, typography, borders, shape and placement.
+- The initial textarea still implies that the user should provide a detailed report.
+- The size of an input communicates the amount of information expected.
+
+## Decision
+
+Retain the useful hierarchy refinements provisionally.
+
+Do not increase reliance on colour.
+
+Defer dark mode and broader palette work.
+
+The next experiment should test whether a smaller starting input better communicates that the user only needs to provide an initial observation.
+
+Do not rewrite previous experiments.
+
+---
+
+### Experiment 07 — Lightweight Starting Observation
+
+#### Hypothesis
+
+A smaller initial input will make beginning an investigation feel easier and will communicate that the engine needs only a concise observation rather than a complete analysis.
+
+#### Questions
+
+- Does the input feel like a conversation starter rather than a report form?
+- Is three to four visible lines sufficient?
+- Does the facilitator panel and input area feel better balanced?
+- Does the user understand that further detail will be gathered through questions?
+- Does reducing the input height make the Analyse action easier to notice?
+
+#### Evaluation
+
+Pending visual review.
+
+#### Status
+
+Experimental.
 
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