log v1 experiments: nineteen cycles, organised by the method that produced them

cycles/    one file per Ishikawa -> scientific method -> Six Sigma loop, named
           for the DEFECT not the fix, carrying the commit record as written at
           the time
findings/  what the cycles produced, cross-cut: live bugs, architecture answers,
           and defects in my own measurement

The organising finding is that predictions which came back FALSE produced every
significant result. Eleven of sixty-one failed, and those eleven found: that the
arity table was not drifted but 40% incomplete; that the AST traversal is
irreducible and only rules and judgments move; that guards could refuse through
the seam after all; and that routing el_bin_lookup through the gate did NOT fix
the SIGSEGV, because the fallback strlen was the hazard -- a wrong fix I would
otherwise have shipped as verified.

One cycle was run without committing predictions first and had to be discarded
as rigged. It is kept, in full, as 18-async-half-expressible.md.

docs/v1/experiments/cycles/17-annotations-are-never-checked.md

@@ -0,0 +1,53 @@
+# annotations are never checked
+
+**Status: verified on `experiment/annotation-checking`, not merged.**
+
+## Ishikawa — why does El silently miscompile?
+
+Three bugs found the same day shared one shape.
+
+```
+method       type tracked by per-function name sets, fed from annotations
+machine      el_val_t erases everything at the C boundary
+material     no propagation through expressions
+measurement  nothing verifies an annotation against what it annotates
+─────────────────────────────────────────────────────────────────────────
+root cause   El has type ANNOTATIONS but no type CHECKING. The annotation
+             feeds dispatch and is never itself verified.
+```
+
+## Predictions
+
+```
+P1  let x: Int = "hello"  compiles clean               expect TRUE
+P2  let s: String = 42    compiles clean               expect TRUE
+P3  the annotation drives dispatch, unverified         expect TRUE
+P4  same root cause as all three bugs found today      expect TRUE
+P5  checking literal-vs-annotation catches both        expect TRUE
+P6  zero false positives across the compiler's source  expect TRUE
+```
+
+## Results — 6/6, and worse than a wrong answer
+
+```
+let x: Int = "hello"; x + 1     →  4343631981   a string POINTER used as an integer
+let s: String = 42; println(s)  →  nothing      address 42 dereferenced as a string
+```
+
+The first **leaks a raw memory address into program output**. The second is an
+**arbitrary-read primitive** if that integer is ever attacker-influenced.
+
+Verified: 6/6, zero false positives across the compiler's own source, fixpoint
+ok, 105/105 native.
+
+## Six Sigma
+
+The emitter only **records** the mismatch; `tools/check/annotations.sh` decides —
+consistent with every other check. Literals are checked because they are
+unambiguous.
+
+**Incomplete, stated not hidden:** only literals. `let x: Int = some_string_fn()`
+still passes, because `signatures.rel` carries Int/Instant/Duration and no
+String entries. That is a data gap, not a capability limit — every El function
+declares its return type in source and codegen already holds `ret_type` on every
+`FnDef`.