Measured the fp8 DiT auto-quant path across the remaining dense-pipeline video families on
B200 (production torch._scaled_mm per-row fp8, no MSLK):
- HunyuanVideo-1.5 (480p + 720p repacks): every frame black (mean luma 0.0, LPIPS 0.82);
int8 is clean (mean 102.7 vs dense 99.9). Same failure as Wan / qwen-image.
- LTX-2: fp8 renders clean (mean 153.7, matches int8's 157.7) -- NOT a black-frame family.
So deny fp8/mxfp8/nvfp4 for hunyuanvideo-1.5 and hunyuanvideo-1.5-720p (fall to int8), and
deliberately leave LTX-2 on fp8. The deny stays measured per family, not a blanket video rule:
a blanket deny would have wrongly forced LTX-2 off fp8. Adds a Hunyuan deny test that also
asserts LTX-2 keeps fp8; 49/49 transformer-quant tests pass.
video_speedmem_bench.py gains guidance_via_guider support (HunyuanVideo-1.5 sets CFG on a
guider component and its __call__ takes no guidance_scale / callback_on_step_end), so the
harness can drive Hunyuan the same way the loader does.
c947b33ef8