I haven't practised TCR much, mostly because I did something similar in the mid-2000s which, I believe, gave me similar benefits. Maybe I'm merely too old and I like my way more. :)
Indeed, chunking happens during ensemble programming and maybe even more effectively, because more people spend more time reflecting and allowing ideas to move from System 2 to System 1. Moreover, the "intelligent input device" approach encourages programmers to articulate what they're thinking as a summary, rather than merely translating from the picture in their head into detailed text in an editor. This articulation provides opportunities to practise that lead to chunking.
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