The mechanisms you name do not fit the measurement. Transport is measured on base checkpoints: Qwen2.5-0.5B and 7B, Qwen3-0.6B-Base, gemma-2-2b, Llama-3.2-1B and 3B, OLMo-2-1B, SmolLM2-360M, pythia-410m. Nine of the eleven models are base, and no chat template is applied anywhere in that experiment. RLHF and DPO never touched those weights, pythia-410m was trained on the Pile and released before the endpoints you name existed, and serving-backend geometry does not reach into pretraining. None of that produces a 0.999 linear map from Qwen2.5-0.5B to OLMo-2-1B.
Your general point is a different matter and it lands. Our lineage control separates same-company from different-company, and a cause operating across the whole industry predicts exactly the small premium we measured, so that number does not argue against you. Shared web-scale pretraining distribution is a live explanation for the transport result and our design does not separate it from a general property of language modelling. That has been inserted into our limitations.
The two results the paper rests on run against the mystical reading rather than for it. Base models do not reach the reported level. Instruction tuning alone adds 0.0786, taking the matched pairs from 0.3649 to 0.4435. Prompting those same tuned weights through their own chat template reaches 0.7272, which is 0.3623 above base, or 0.2837 taken as the marginal step over the untemplated instruct arm. On either contrast the format term is several times the weight term. Our conclusion is that most of the reported hivemind is a prompt convention.