Code-quality review caught that the kernel header described the τ
shift as 'toward the dense tail' but the actual math
(`t = default + skew × SKEW_SHIFT`) shifts τ in the SAME direction
as the skew sign — i.e. toward the LONG (sparse) tail, not the dense
region.
For a left-skewed distribution (long left tail, mode + dense mass on
the right), skew < 0 → τ shifts down toward 0 → IQN samples more of
the LEFT tail (sparse). The intent is risk-aware quantile coverage:
when there's tail mass that the symmetric 5-tuple under-represents,
lean the grid toward that tail. This matches risk-aware IQN where
financial risk modeling cares about downside coverage.
The math is correct and faithful to the plan's formula; only the
prose description was reversed. Replaced the one-liner with a 7-line
explanation that names the actual semantic clearly ('leaning the
quantile grid INTO the asymmetry direction').
Comment-only change. Cubin rebuild clean.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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