Grasp-SFT route C — joint step 2000, flow head on training seeds

Checkpoint fontaine_grasp_sft_joint_corrected/step_002000 (the unseen-leg page's checkpoint, flow head served on the training band) · euler-10, execute-horizon 30, seeds 1000–1099 — the stage-B collection band the 313-demo SFT corpus was drawn from (64 kept / 36 collector-rejected among these 100 scenes) · leg 2 of the probe chain, finished 09:47Z 08-16, ~1.4 GPU-h (registered A §4: unseen 0–99, then train band 1000–1099) · headline: 42/100 ≈ the unseen sibling's 44/100 — no memorization signature; kept 29/64 vs rejected 13/36, CIs overlap (split section below)

42/100
successes (≤3 cm, held)
9 / 44
anchors: base / unseen sibling
75/100
moved the boat >0.5 cm
3.86 cm
mean progress toward disk
0
reset strikes

Against the anchors

Memorization split: kept vs collector-rejected scenes

Membership from the banked stage-B collect curve's kept_seeds: a kept training seed contributed a demo to the 313-demo SFT corpus; a rejected seed's scene was attempted but the scripted collector failed there, so the model never saw it (and those scenes skew harder — the rejection reason confounds the arms' gap). The decisive read is kept vs unseen: 29/64 (45%) on scenes the model trained on vs 44/100 on scenes it never saw — no memorization signature; the checkpoint generalizes rather than replays. The kept−rejected gap (+9 pp) sits well inside the overlapping Wilson CIs.

29/64
kept arm (45%, CI 34–57%)
13/36
rejected arm (36%, CI 22–52%)
+9 pp
kept − rejected rate gap (CIs overlap)
44/100
unseen sibling — the anchor the kept arm must beat to claim memorization
4.45 vs 2.82 cm
mean progress, kept vs rejected

Per-seed outcomes

Clips

fastest success (kept arm) — seed 1027, final 4.0 cm, success at tick 90
median success (kept arm) — seed 1017, final 2.5 cm, success at tick 135
nearest miss (kept arm) — seed 1008, final 1.5 cm
fastest success (rejected arm) — seed 1092, final 4.0 cm, success at tick 106
nearest miss (rejected arm) — seed 1073, final 6.0 cm

Per-seed table

seedspawn cmmin cmfinal cmprogress cmsuccess
10008.92.42.46.5✓ @ 126
100111.63.43.48.2✓ @ 138
10029.94.87.85.1—
100310.41.91.98.5✓ @ 133
100411.21.71.79.5—
10057.65.75.91.8—
10068.82.42.46.4✓ @ 209
10078.11.51.56.5✓ @ 117
10087.91.41.56.5—
100910.210.110.10.1—
10109.38.98.90.4—
10119.01.72.27.3—
10128.08.08.00.0—
101311.710.912.40.7—
10148.91.11.27.8✓ @ 639
10158.87.88.50.9—
10169.58.78.80.9—
10179.02.52.56.5✓ @ 135
10189.78.28.31.4—
10199.89.39.40.4—
102010.42.02.08.4✓ @ 138
102111.11.41.49.7✓ @ 136
10227.81.51.56.3✓ @ 117
10237.46.87.30.7—
102410.33.93.96.4✓ @ 119
10259.44.04.05.4✓ @ 127
10268.91.82.57.1—
10279.34.04.05.3✓ @ 90
102810.43.43.47.0✓ @ 147
10298.75.89.82.8—
103011.411.411.40.0—
10317.76.47.51.3—
103211.211.212.60.0—
10338.48.49.10.0—
103411.811.111.10.8—
10359.83.53.56.3✓ @ 650
10367.97.77.70.2—
103710.12.32.37.8✓ @ 111
103811.14.86.06.2—
103910.22.12.18.0✓ @ 138
10408.88.88.80.0—
104110.610.610.60.0—
10429.81.91.97.9✓ @ 128
104311.14.04.07.1✓ @ 146
10448.04.04.04.0✓ @ 111
104510.99.913.21.0—
10468.18.19.70.0—
10479.73.63.66.2✓ @ 287
104811.42.22.29.1✓ @ 137
10499.12.22.56.9—
105010.22.32.37.9✓ @ 122
105111.19.89.81.3—
10529.32.62.66.7✓ @ 137
105310.810.810.80.0—
10548.25.55.62.7—
105511.69.510.42.1—
105611.82.62.69.2✓ @ 123
10579.33.23.26.2✓ @ 208
105811.01.41.89.6✓ @ 236
105910.12.52.57.5✓ @ 128
106012.111.111.11.1—
10619.39.09.00.2—
106211.011.011.00.0—
10639.24.810.04.4—
10649.61.71.77.9✓ @ 134
106511.711.711.70.0—
10668.52.02.06.6✓ @ 128
10678.53.03.05.4✓ @ 125
10688.88.215.90.6—
10698.93.93.94.9✓ @ 152
10707.26.56.70.6—
10717.67.07.00.6—
10728.57.619.40.9—
10737.35.86.01.6—
107411.12.42.48.7✓ @ 135
10757.97.88.40.1—
107610.52.32.38.2✓ @ 346
107712.111.711.70.4—
107811.69.516.62.1—
10798.63.73.74.9✓ @ 120
10808.82.22.26.6✓ @ 125
10817.47.37.70.0—
108210.310.310.30.0—
10837.96.66.61.3—
108411.94.04.07.9✓ @ 149
108510.29.79.70.5—
108611.511.511.80.0—
108711.210.910.90.4—
108811.511.412.00.0—
10898.16.86.81.3—
109011.011.011.20.0—
109111.03.63.67.4✓ @ 102
109210.04.04.06.1✓ @ 106
10939.69.49.40.2—
109410.910.210.20.8—
109510.21.53.38.7✓ @ 836
10968.88.88.80.0—
10979.26.97.32.3—
10989.92.22.27.7✓ @ 140
10999.33.93.95.4✓ @ 111

Regenerate: fontaine/scripts/grasp_sft_joint_unseen_report.py from the banked flow_train.json only.