Retitle: lead with method + separate working frozen heads from collapsed CD4-native negative

README.md

@@ -12,16 +12,29 @@ tags:
 - state-model
 ---
 
-# RefineRx — CD4-native STATE transition model with fused adaptive-depth halting
-
-RefineRx is a perturbation-response model built on the ARC **STATE** transition
-architecture, extended with a **fused adaptive-depth halting** mechanism
-(learned, per-perturbation refinement depth). This repository ships:
-
-- the **CD4-native** transition + fused-halting checkpoints (trained from scratch
-  on CD4+ T-cell pseudobulk), and
-- four **oracle-ACT halt heads** trained on frozen Replogle cell-line STATE
-  embedding (ST-SE) backbones.
+# RefineRx — adaptive-depth halting as a per-perturbation signature on STATE
+
+RefineRx adds a **learned, per-perturbation adaptive-depth halting** mechanism to
+the ARC **STATE** perturbation-response architecture, and asks whether the
+resulting halting depth E[N] is a reproducible, effect-size-independent signature.
+This repository ships both the **positive** and the **negative** result of that
+question:
+
+- **✅ Positive (the working artifacts): four `oracle-ACT` halt heads** on **frozen**
+  Replogle cell-line STATE-embedding (ST-SE) backbones. Read off a fixed,
+  gradually-refining backbone, these recover a usable per-perturbation depth
+  signature (reproducible within-line, effect-independent, non-redundant with
+  network topology).
+- **⚠️ Negative (documented, for the record): CD4-native fused-halting checkpoints**
+  trained from scratch on CD4+ T-cell **pseudobulk**. The response head fits, but
+  the halting depth **collapses to a constant** on this pseudobulk substrate — see
+  the key result below. These checkpoints are shipped as the reproducible negative,
+  not as a recommended depth model.
+
+> **Naming note.** "CD4-native" refers only to the from-scratch pseudobulk
+> checkpoints in `checkpoints/`; it is the *collapsed* model. The usable
+> depth signal in this repo comes from the frozen-backbone halt heads in
+> `halt_heads/`.
 
 **Paper:** *When Does a Perturbation Model Know Enough? Learned Halting as a
 Biological Model Readout* (Yash Raj).