The batch training path (select_actions_batch → forward()) does NOT
increment DQN::total_steps. Only select_action() does. When
warmup_steps > 0, train_step() checks total_steps < warmup_steps
and returns (0.0, 0.0) — zero loss, zero gradients. The model
never trained; "results" were random initialization Q-values.
Fix: force warmup_steps=0 in hyperopt adapter and remove
warmup_ratio from the 31D→30D search space (saves a dimension
for TPE/PSO effectiveness).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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