Based on kernel deep dive: 1.56% occupancy on H100 from 1-warp/sample architecture, 46KB stack spill, 47 kernel launches per step. 7 tasks: cuBLAS forward, batched backward, fuse BF16/EMA, multi-block prefix sum, C51 loss kernel, H100 profiling. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>