150e3bd9fd
Full diagnostic chain (synth→real zero-shot→real finetune→held-out) shows the TS-modality approach works in-distribution but fails to generalize across entities: same SMD dataset, same 38 channels, just a different machine (1→2) collapses output to repetition garbage. Root cause is the lightweight TS encoder (2-layer TF, 2.1M params) learning dataset/machine- specific patterns rather than transferable time-series representations. This is a valuable negative result: it cleanly rules out the '0.5B LLM + 2-layer TS encoder + single-distribution synth training' route for general time-series understanding, which is more credible than any 'looks like it works but never tested cross-domain' result. Records: - tasks.md: M6 diagnostic section (6.1-6.5) with evidence + archive decision - proposal.md: Status header flagging archive + pointer to diagnosis - docs/diagnosis-2026-07-02-cross-domain.md: full evidence chain, root-cause analysis, capability boundaries, asset inventory, restart conditions Project status: archived. Code/data/checkpoints/reports preserved. Restart requires any of: (1) larger encoder + real-data from-scratch training, (2) channel-agnostic patch strategy, (3) multi-dataset joint training with held-out-dataset generalization proof.