Determine the trigger of the second modular lock-in jump

Determine whether the second lock-in jump in task-overlap structure is triggered by an intrinsic second lock-in, a supply-ratio inflection, or a data-order cluster.

Background

The dominant-pair overlap exhibits two sharp transitions during training. The second transition is the largest event in the trajectory, but its magnitude does not track the learning-rate schedule closely enough to identify the cause.

The paper therefore retains three candidate explanations: an intrinsic second lock-in caused by threshold accumulation, an inflection in the relative gradient-supply ratio, or a cluster in data order. No adjudicating experiment has yet been conducted.

References

Its trigger therefore remains an open candidate set—an intrinsic second lock-in, a supply-ratio inflection, or a data-order cluster (Appendix~I).

— Pre-carved Niches: The Formation Dynamics of Modular Task Partitions in Early LLM Training  (2609.01170 - Li et al., 1 Sep 2026) in Section 5.1, “A two-jump structure, not gradual growth”