Binary-search a runtime bug

For a large script:

1. Preserve a copy/commit.

2. Reproduce the issue reliably.

3. Disable half of the relevant call path with a temporary gate.

4. Test whether the issue remains.

5. Repeat until one subsystem or writer remains.

6. Restore surrounding code and fix the actual ownership/order bug.

Use line comments for temporary disabling when blocks already contain /* */ comments.