The four generated initial-condition providers are now supported. ic_gen and spectral_random_velocity cite the measurement that already covered them, and the two wall-bounded providers were measured against their contract (wall-spectral-ic-2026-09-22): on stretched channel and duct grids the staged field carries the requested bulk velocity and perturbation RMS exactly, its mean equals the flux-normalized product parabola to 3e-15, the walls carry zero velocity, and the flux field the runtime reconstructs is divergence-free at round-off. They remain startup constructions: nothing here establishes sustained turbulence.
RANS is removed and returned to planned. models.physics.turbulence.rans is refused at validation and -rans at setup; both name the status rather than ignoring the setting. Nothing behind the selector was ever implemented - the K_Omega fields were never allocated, the transport update in FlowSolver was commented out, and the function it called was defined nowhere - so a case that enabled it aborted on a null vector at the end of the first step. It was recorded known-defective on 2026-09-18; since no implementation had ever existed, removing the dead hooks returns it to planned, with the charter for a future closure on page 57 and the removed hooks listed in src/guide.md.
Removed with it: the K_Omega fields and their catalog entries, the FIELD_AVAILABILITY_RANS flag, the two-component DM they alone used (never created), the simCtx->rans branches in the RHS, run loop, checkpoint I/O and Newton-Krylov scope check, and the k_omega capability value.
Checkpoint metadata: -checkpoint_rans is no longer written or required. The format version is unchanged, so existing checkpoints still load; a checkpoint written now is not readable by a pre-removal binary, which requires that key.
Wall functions are unaffected, being configured independently of any closure. Only the two pairing refusals that named RANS (cabot and werner under it) went with the selector.
A subsystem may now move from known-defective to planned, with a recorded reason saying what was found and what was removed: a feature that never existed is not a feature that broke.