> The average person can hold roughly four such chunks in working memory. Once the cognitive load reaches this threshold, it becomes much harder to understand things.

This is a paraphrase of the scientific meaning. "Intrinsic" and "extrinsic" cognitive load are also terms of art coined by John Sweller in his studies of working memory in education.

I agree the article isn't designed to be peer-reviewed science. And I agree the article has real insights that resonate with working developers. But I'm also a fan of honesty in scientific communication. When we say "vaccines prevent disease", that's based on both an enormous amount of data as well as a relatively precise theory of how vaccines work biologically. But if we say "composition reduces cognitive load", that's just based on personal experience. I think it's valuable to separate out the strength of the evidence for these claims.