Theses 06 / 19 QUALITATIVE published 05 Apr 2026 · updated 17 July 2026 · v43

Harness Engineering

The quality of the harness — the tooling, orchestration, and workflow wrapping around a model — matters as much as or more than the model itself. entity/ben-thompson validates this: "model only as good as the harness." Empirical data shows Opus 4.5 performing ~20% higher in Cursor than in Claude Code, demonstrating that the harness creates large practical differences even when the underlying model is identical.

No market basket

This thesis is qualitative — its evidence lives in the signals feed and the research system rather than a price series.

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When we're wrong

One thesis is currently moving against us — Agents as Primary Users, +9.3% since published. It stays on the board. We update priors on evidence, not on evidence we went looking for.