Verified duplicate rather than assumed one. Section for section it is the same skill as `tdd` — Overview, When to Use, Iron Law, Red-Green-Refactor with the same dot graph, Good Tests, Common Rationalizations, Red Flags, Verification Checklist, When Stuck, Final Rule — with TypeScript examples and obra's "your human partner" phrasing instead of ours. `tdd` carries all of it plus the Go-specific material (table-driven tests, t.Run, testify, go test -race), the brain MCP integration and the Mode 2 routing note. Its one non-SKILL.md file, testing-anti-patterns.md, is byte-identical to skills/tdd/references/testing-anti-patterns.md, which `tdd` already points at. Nothing was salvageable because nothing was different. No references anywhere outside its own directory except the index row, removed here. `atdd` is untouched — acceptance-level is a genuinely different altitude and it already cross-refs `tdd` correctly. Incidentally the first live catch by bin/check-index (#15): deleting the directory turned `task check` red with "SKILLS_INDEX.md lists 'superpowers-test-driven-development', which has no ...SKILL.md" before I got to the row. 42 skills now. Closes #13 Bump-Type: patch