The quadratic Armey Curve predicts impossible negative growth rates at high spending levels and requires an upturn at low spending levels that simply does not appear in the data. The power law model (growth = β₀ × spending⁻ᵅ) achieves R²≈0.42 vs 0.39 for the quadratic across 113 countries, has lower AIC, and is monotonically decreasing — matching the actual cross-country pattern without producing mathematical artifacts. Power laws are also theoretically coherent: the braking force of government spending should be scale-free, not bell-curve-shaped.