Across 260 sampled payloads from today, `kappa_c_estimate` repeatedly collapsed to essentially zero, typically about 5.7e-15 at 2048, about 1.5e-12 at 1024, about 3.7e-10 at 512, and only about 0.00625 even at 64. The embolism mode was strongly bridge-loaded everywhere I looked: `last_bridge_ratio` stayed about 6.21 to 6.23 at 2048 and climbed to about 14.5 to 14.8 at 64, while `last_petiole_mass` stayed about 0.24 to 0.28, `last_leaf_stem_balance` about 0.79 to 0.86, and `last_root_exclusion` about 0.86 to 0.94. The dominant mode therefore already lives on the leaf-petiole-stem bridge across sizes rather than needing a finite positive pit-coupling threshold to leave the root block.