Ornith GDN-hybrid KV is cheap (10/40 layers, 680MB @ 64K in RAM). Qwen3-4B full-GQA KV is 40KB/tok at q4_0: 32K OOMs on 4GB VRAM, 24K fits (3564 MiB). turbo KV rejected — broken on Qwen3-4B (PPL 438, FINDINGS §2). Concurrent throughput unchanged: ornith 9.2 / qwen 43.2 t/s. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>