This is the page where I overturned my own headline. The Granite page shipped with a clean champion; a better instrument erased it. The mechanism work survived untouched — and the constructive findings that replaced the leaderboard are more useful than what they replaced, and they appear to generalize.
§1The mechanism wasn't the problem — the leaderboard was
The instrument-dependence cuts cleanly. What evaporated was the leaderboard layer (which configs win, and why). What stands, because none of it was instrument-dependent, is the whole mechanism stack: direction-is-read / magnitude-is-discarded, the U-shaped depth-vulnerability curve, RYS-dup-as-power-iteration, the ~4-layer circuit-coherence length, the steering / soft-abliteration results, the continuous-depth ODE framing. The page keeps every one of those.
So the page gets a walkback banner on combo_10_38 — and, more usefully, a constructive
section to replace the leaderboard it lost. The rest of this addendum is those four findings.
§2Finding 1 — capability is a few flipped bugs, not a risen tide
Granite's no-CoT arithmetic baseline
doesn't fail randomly; it fails deterministically, in a handful of
specific, reproducible ways. 907 − 131 (= 776) never comes back right across 15 seeds. It
settles into one of two stable wrong answers: 676 (9/15, a hundreds-column slip) or
131 (6/15, echoing the subtrahend). 0 of 15 correct, two error basins. A particular carry-drop on
an addition probe, likewise. I call these metastable bugs: observation
the 0/15 reproducibility is what's measured; interpretation "basin / attractor" is
the interpretation.
A "winning" surgery doesn't lift a diffuse competence: it flips a few of these specific bugs to 12/12 right. The measurement trap is that a balanced 49-probe average dilutes a concentrated flip until it looks like a tiny effect. The small balanced t-stats badly understate what's happening, and that's correct behaviour, not a measurement failure. The win really is concentrated. The right lens is per-probe: which exact bug got fixed, and how many configs reach it.
↳ the action is discrete bug-flips; the 49-probe average is exactly what hides it
907−131→776 settles on two error basins (676 / 131). Row-aligned: a log bar of "# configs that fix this probe," showing the bimodal split — easy probes fixed by ~85–305 configs, rare-fix specialists by 2–7.§3Finding 2 — separated treatments stack; proximate ones mask
Once you know wins are disjoint bug-fixes, composition has an apparent rule and a non-obvious failure mode. observation depth-separated treatments tend to stack; same-region or redundant ones mask. I'm calling this a heuristic, not a law (earning the stronger word would take a regression of effect against layer-distance plus an effect-size distribution, and the margins below are thin).
| Pair | Depth gap | Result | Reading |
|---|---|---|---|
dampL5a130 + pr26 | 21 layers | math 0.570, paired t +6.4 vs baseline | best math result of the entire sweep — edges prune_26 alone (0.566). Compose without interfering. |
dampL6a70 + pr26 | 20 layers | clears prune_26 on core probes; a hair under on full 49 | depth-separated, roughly additive — but the margin over its best component is inside the noise. |
pr26 + dup16 | near | falls below prune_26 alone | observation combining loses ground. interpretation overlapping fixers reach for the same bugs, don't compound. |
The recipe for a constructive profile: compose per-layer treatments
that are (a) depth-separated AND (b) fix disjoint probes — and the per-probe autopsy (Finding 1) is
exactly what tells you which fix which. This generalizes the Gemma cross-zone superadditivity (writer-zone ×
consumer-block) and adds its failure mode, which Gemma never made explicit: redundancy
near in depth appears to dilute rather than compound. The emerging data-driven math profile that falls out:
L5↑(α1.3) + L26↓(prune or α0.15) + L14↑(α1.8), all depth-separated, predicted to stack.
Held-out-seed validation is the open next step; argmax off noisy
per-layer curves overfits, so the profile must be confirmed out-of-sample before it's a claim.
↳ depth separation is the axis that decides whether two surgeries add or interfere
§4Finding 3 — the 3-point map lies; non-monotone layers need the fine grid
The published page reads layers through a prune/dup endpoint map. That skeleton is
blind to any layer with a U-shaped α-response, and Granite has them. L6 peaks at
α≈0.7 (+0.062 Δ-vs-baseline on the gcore in-band probes, n=348/point: the top single-site math
move) while both prune_6 (α=0, removed outright) and dup_6 (α=2,
−0.105) collapse it. A gentle damp is neither endpoint, so the 3-point map can't see it: it reads L6 as
"touch it and it dies," when in fact a partial damp is the single best thing you can do there.
L5 similarly peaks at α≈1.3.
This sorts the layers into two math populations: damp-down layers (L7/8/10/18/26/27 want α<0.5 — L26 is the "savant," optimum monotone toward zero, where a heavy partial damp ≈ pruning it without removal) and boost layers (L9/14/15/16/19/21/22/24/29/34 want α>1). Any per-layer sensitivity claim needs the dense single-pass α grid (~0.5–1.5), not the dup/prune endpoints.
The boost layers cap at ~α1.5, and the obvious move to push past it is to spread the gain across
k damped passes. It fails: L22 and L34 each peak at single-pass α1.5, and spreading α>1.5
across k passes overshoots rather than extending the ceiling (sa22_S160_k6 d−0.022,
sa34 d−0.07). The "k-split rescues α>1.5" hypothesis is refuted at these sites — stated
plainly because it's the obvious thing to try.
↳ the endpoints draw a falling line; the dense grid finds an interior peak the endpoints can't
§5Finding 4 — the Σα-law transferred, with the predicted downshift
Granite was the cross-model confirmation of the Σα-law first found on
MiniCPM5. The governing variable for a stacked/damped layer is
Σα = the sum of all per-pass alphas; k (copy count) scales the magnitude, Σα sets the
sign. On Granite the peak sits at Σα ≈ 0.75 versus MiniCPM's ≈1.25,
and that downshift was named in advance: the pre-run note (2026-06-12, before the
fair-battery run executed) flagged Granite's residual_multiplier = 0.22 as the suspect, and
the run confirmed Σα≈0.75.
interpretation The working mechanism: a smaller per-layer residual write means a
lower cumulative-α budget before the residual leaves the norm band. Beyond peak: ≈2.0 fading, ≥3
cratering, the same one-death-two-doors collapse. observation over-drive and
negative-α both produce digit / special-token / CJK leak; interpretation residual-norm
corruption is the proposed cause. dampall is neutral-to-negative on Granite (it isn't a
collapsed model, so there's no pathology to relieve) — control behaviour consistent with MiniCPM's
dampall "wins" having been de-collapse, not capability.
↳ the leftward shift of the peak is the whole visual argument — one law, two models
residual_multiplier = 0.22 as the named-in-advance cause; the shared ≥3 crater zone is marked.Caveats
The mechanism work here is solid (re-checked against the v3 results file, and unrelated to what follows). What's still open is the constructive side: the profile and the stacking heuristic that replaced the old leaderboard are early reads off noisy per-layer data, not confirmed findings yet.
- The constructive profile (
L5↑+L26↓+L14↑) is not yet held-out-validated. Present it as the emerging endgame, not a confirmed champion — argmax off noisy per-layer curves overfits. - The stacking heuristic lives on the in-band / gcore probes, not the floored/ceilinged 49-probe mean. One combo marginally beats its best component, one masks — suggestive, not established. It's a heuristic, not a law until there's a regression of effect against layer-distance.
- The fair reading of the retired eq/mc leaderboard: Granite is balanced-resistant (nothing clears the multiplicity bar), but channel specialists exist: interior damping moves math, specific prunes move MC, and EQ is essentially unmovable (never collapsed, so there's no headroom to recover).
- CoT remains unrun on Granite (it decodes ~250 tok/s vs MiniCPM's ~1500 — an est. 10–20 h sweep, gated on a smoke test). The open question that would close the line: does reasoning fix the same metastable bugs the surgery does (redundant) or different ones (compound)? Compare fix-sets via the swing board.
Granite is the dense-model + steering branch of the line. Measurement → the methods writeup. The Σα-law it confirms was born on MiniCPM5. The "I overturned my own result" register is shared with the HRM specimen, which paid for the same instrument lesson first. Sibling specimens: Gemma 4 (whose cross-zone superadditivity this generalizes), the MoE fork. Boards and raw data: monitor.py::swing_probes(), granite_nocot_v3_da50cdae_results.jsonl. Run locally on a 16 GB Mac Mini.