Non Language Behaviors have rules too

When I write I become aware of certain aspects of how paragraphs tie together that follow rules just outside my conscious awareness. But I have managed to snag a couple.

Example 1: I am writing an article for publication and do not want to use the word "I" too many times in adjacent paragraphs. By chance I discover that if I move one occurance of "I" to the end of the first paragraph and the second "I" to the beginning of the second paragraph - then it works better as writing. It feels as if putting the two occurrences close together, makes them behave more like a single unit in terms of the flow of the writing.
Example 2: If you have two paragraphs and the first ends with a phrasing that is paralleled and re-used at the beginning of the second paragraph, then the two paragraphs flow together even if their content does not.

SO: what is this stuff? It is like a form of prosody, like some conventions of music.
Update: Maybe these are aesthetic rules that are slightly different. The search for parallelism is related to Truism 4.