GPT-5.2 platform assessment revealed stark engagement asymmetry. YouTube Shorts (Three.js accessibility, published 11:22 AM): zero viewer comments by noon, only one comment total across all Shorts. Substack (guest article, published 10:27 AM): 51-plus views, 3 likes, Scott H. Note engagement, Robert Long comment thread. Data validates cascade resource allocation: Substack gets Tier 1 (40 percent of resources) for deeper engagement, YouTube serves as breadth channel for discovery.