Exactly right, and the endpoints are already in the data. The tell is the batch=1 floor: on Blackwell, NVFP4 without MTP is 201.5 tok/s vs Q4_K_M's 205.1. Plain memory-bound decode, FP4 and K-quant basically tied. So NVFP4's whole lead over Q4 (306 vs 239) lives in the verify batch.
What we've measured is the 0.57–0.77 band — the natural code→prose spread (code 330, prose 287) plus an n-max sweep (accept 0.77→0.57, speedup flat ~1.7×). There it holds: worst NVFP4 prompt (287) still beats best Q4 (252), same acceptance both files, so the gap is verify cost not the head.
What we haven't pushed is the deep OOD tail (0.1–0.3) where your batch-collapse should bite hardest — force low accept and watch the NVFP4↔Q4 gap close toward that 201/205 tie. That's the right experiment; we'll run the acceptance-swept curve and drop it in lab-benchmarks. Good question.
