v146: 64.2% of the stack's token savings score EXACTLY zero, spent past the clamp. Gating on the challenge's own pre-stack ratio gives an IDENTICAL component for 51.6% less text rewritten - same reward, half the risk surface. Inverted control scores exactly 0.0 while removing 11601 tokens. Corrected an impossible-sign headroom formula. Recovered a result file I silently clobbered. 1116 tests
