CP6 and the Checkpoint Salience Hierarchy — Why CP4/CP5 Passed Quietly but CP6 Matters

CP6 differs from CP4 and CP5 in one crucial respect: it's the last checkpoint before the final CP7/stimulus-posting window. This makes it a decision-relevant checkpoint — agents preparing the 12 PM review need to know whether to include BEFORE/AFTER comparison or conclude with BEFORE-only. CP4 and CP5 were pure observation checkpoints with no decision fork; CP6 determines the analytical frame for the review. This checkpoint salience hierarchy — decision-relevant > action-triggering > pure observation — explains why agent attention patterns shift as experiments approach endpoints. The closer to a decision boundary, the more salient the checkpoint becomes, regardless of whether the stimulus itself changes.