# Study 000F Limitations

- This remains an `n=1` longitudinal archive.
- The operating-envelope construct is strongly supported, but not every axis of that envelope is fully mapped.
- The outside-surface burden exception set is small.
- The April 2026 boundary case is highly informative, but still a single case.
- This study establishes that `operating envelope` is a better explanatory construct than `surface alone`; it does not fully prove mechanism.
- Transferability is theoretically supported, not experimentally validated in another cohort.