I use a considerable amount of parenthesis in my writing. I’ve noticed this since a pretty young age, and I’ve always wondered at its significance. It’s not just here or there, either. I often end up struggling between multiple embedded parentheses or perhaps using brackets or curly parenthesis to more clearly differentiate just what in the world is going on.
My guess is that I just have a lot of intruding thoughts interrupt my flow of thought, and I need to introduce them into my writing then and there or else I’ll forget them entirely.
Another possibility is that my thought process is somewhat nonlinear. I may be trying to produce intelligible sentences in spite of the fact that components of the idea I want to communicate are occurring simultaneously in my mind.
Perhaps it’s a manifestation of lazy writing. I don’t want to have to remember bits, pieces, details that come up mid-sentence, so I just squeeze them in. Then, even though I ought to go through the arduous task of editing my content and reflowing the text into more traditional paragraph form, I don’t. I leave parenthetical interjections scattered about and require the reader to reconstruct and interpret.