pub const MAX_F16_TWIN_K: usize = 16;Expand description
Widest chain-verify K with an FP16 h-state twin
(gated_delta_rule_wy{5..16}_f16).
The SSOT for “can this verify width run under the f16 pool”. K=17 — the DFlash arm at gamma 16 — has no twin, and the FP32 wy17 kernel over an FP16 h-state emits fluent garbage rather than faulting, so the CLI validator and the serve preflight both gate on this instead of a literal.
Expressed as K, not gamma: the DFlash verify width is gamma + 1, and conflating the two is how the width check came to admit gamma 16 (K=17, no twin) while its message claimed to cover “widths 5..16”.