Verifies that when one direction's centered advantage dominates
strongly enough, action selection picks it deterministically across
all N=1000 Philox-keyed runs.
Plan specifies "Thompson temp = 0.0 → pure argmax E[Q]", but the
kernel floors thompson_temp at MIN_TEMP=0.5 per
pearl_blend_formulas_must_have_permanent_floor — pure τ=0 isn't
ISV-accessible. With τ=0.5 the blend is q_eff = 0.5·E[Q] +
0.5·q_sample; deterministic argmax across all τ=0.5 draws requires
the E[Q] gap to exceed atom_span/2.
Construction: NA=3 atoms [-0.1, 0, +0.1] (atom_span=0.2). A_dir
puts +300 at z=2 for Long, -100 at z=2 for others (per-atom mean
zero ⇒ centering preserves shape). Long centered E[Q] ≈ +0.1, others
≈ -0.05 (gap 0.15 > 0.1). q_sample[Long] = +0.1 with prob ≈ 1
(softmax(300) ≈ delta at z=2); q_sample[other] ∈ {-0.1, 0} (zero
prob for +0.1). q_eff[Long] = 0.1; q_eff[other] ≤ -0.025. Long
strictly wins all draws.
If the centering breaks (Long no longer dominant under centered E[Q])
or τ blends a non-Long sample over Long, this test fires.
Plan: docs/superpowers/plans/2026-05-08-sp17-dueling-q-network.md
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>