paper v2.31: matched 30-epoch BP/DFA controls (was unsourced 0.609/0.308)

The §5 ¶3 BP-no-penalty value of 0.609 ± 0.004 and DFA-no-penalty value
of 0.308 ± 0.014 turned out to be unsourced — they were carried over
from a hardcoded comment in experiments/bp_with_penalty_control.py
("BP-trainable (3-seed mean): 0.609") that nobody had actually measured
with a matched 30-epoch run.

Ran the missing matched controls under the same recipe as BP+pen
(lam=0, 30 epochs, AdamW 1e-3, wd 0.01, cosine schedule, batch 128,
3 seeds 42/123/456):

  BP no-pen 30ep: per-seed 0.5851, 0.5845, 0.5863  →  0.585 ± 0.001
                  (paper said 0.609 ± 0.004, off by 0.024)
  DFA no-pen 30ep: per-seed 0.3070, 0.2985, 0.2966 →  0.301 ± 0.005
                  (paper said 0.308 ± 0.014)

Also re-grounded DFA+penalty 30ep using the dfa_pen_short 3-seed run
(0.3593, 0.3610, 0.3604 → 0.360 ± 0.001), which is what the deep-cosine
+0.155 figure was computed on. The paper had 0.363 ± 0.001 — that came
from the 100-epoch run, not the 30-epoch run, so it was an apples-to-
oranges comparison with BP+pen 30-ep.

Paper changes (§5 ¶3):
  BP penalty cost:  -8 pp  →  -5.5 pp
  DFA pen rescue:   +5.5 → +5.9 pp
  DFA+pen margin vs frozen: +1.4 → +1.1 pp
  BP-to-DFA gap:     17 → 17.0 pp (unchanged)
  BP-to-SB gap:      7.7 → 7.7 pp (unchanged)
  BP-to-DFA gap is still the lower-bound credit-quality cost claim;
  17 pp gap is unchanged in magnitude.

Also updated:
- §5 ¶1 prose: 0.363 → 0.360, 0.308 → 0.301
- §4 ¶4 prose: DFA+pen 0.363 → 0.360
- Appendix J Table 9 caption: 0.363 → 0.360, +9.0 → +9.3 pp gap to SB
- Appendix L paragraph: +5.5 → +5.9 pp DFA penalty rescue
- Figure 3 panel C bar values + title pen-cost annotation
- New results/matched_30ep_control_summary.json as auditable record

Page layout preserved: 9 main pages + refs p10, 18 total, 0 overfull.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

1 files changed, 37 insertions, 0 deletions

diff --git a/results/dfa_nopen_30ep_3seed.log b/results/dfa_nopen_30ep_3seed.log
new file mode 100644
index 0000000..ec99d88
--- /dev/null
+++ b/results/dfa_nopen_30ep_3seed.log
@@ -0,0 +1,37 @@
+Using device: cuda:0
+
+============================================================
+Seed 42
+============================================================
+
+--- DFA ---
+  [DFA] Epoch 1: loss=2.0412, train=0.2521, test=0.2899
+  [DFA] Epoch 10: loss=2.0028, train=0.2715, test=0.2862
+  [DFA] Epoch 20: loss=1.9912, train=0.2790, test=0.3047
+  [DFA] Epoch 30: loss=1.9860, train=0.2825, test=0.3070
+  Final test acc: 0.3070
+
+============================================================
+Seed 123
+============================================================
+
+--- DFA ---
+  [DFA] Epoch 1: loss=2.0435, train=0.2482, test=0.2683
+  [DFA] Epoch 10: loss=1.9956, train=0.2738, test=0.2943
+  [DFA] Epoch 20: loss=1.9844, train=0.2785, test=0.2986
+  [DFA] Epoch 30: loss=1.9814, train=0.2828, test=0.2985
+  Final test acc: 0.2985
+
+============================================================
+Seed 456
+============================================================
+
+--- DFA ---
+  [DFA] Epoch 1: loss=2.0539, train=0.2465, test=0.2591
+  [DFA] Epoch 10: loss=2.0115, train=0.2637, test=0.2887
+  [DFA] Epoch 20: loss=1.9990, train=0.2728, test=0.2941
+  [DFA] Epoch 30: loss=1.9955, train=0.2767, test=0.2966
+  Final test acc: 0.2966
+
+All results saved to results/dfa_no_penalty_30ep/results_cifar10.json
+=== DONE ===