Probably an instance of:
"The Reversal Curse: LLMs trained on "A is B" fail to learn "B is A"
"The Reversal Curse: LLMs trained on "A is B" fail to learn "B is A"
The point their making in that paper reminds me of this paper some people shared around work earlier this year, https://arxiv.org/pdf/2512.14982 (Prompt Repetition Improves Non-Reasoning LLMs)... I wonder how OPs question would fare (or the questions presented in the paper you posted) given double repetition.
If you consider how the attention mechanism works then a very hand wavey intuition is that despite being entirely arbitrary additional tokens should still provide the opportunity for additional information processing.