We should write how we speak, right?
Or, I guess it depends on who you're writing to and what, but that is the devil's advo-marketer in me that pipes up.
See, I didn't put the above in parentheses because we don't speak in asides--we take people aside and tell them privately.
"I didn't want to tell you in the meeting, but your fly's undone."
Or we gossip--and even that feels more like a whisper-exclamation point if I had to make one.
...oh and I mention that she's sleeping with him AND his son?!
It doesn't feel right to make all that racket behind brackets.
A random some-months ago, I gave myself a trial run to ditch the parentheses. I can't remember the exact moment, but it was probably some innocuous misplacement of the curves that got on my nerves--like when one loses their shit when they find for the final time that their soon-to-be-ex lover left the stove on low. It might have been an accident, but they got burned.
So how did it work? I still wrote what would be inside the parentheses, I would just leave the phrase naked, for all the world to see. Or if it was unnecessary, I would simply omit it. It was really a test in my own self-editing, knowing that if I put the line in a box, I will still need to carry it. So call me a minimalist, or maybe an over-stater, but six months-to-a-year later, I'm still parentheses-free. I highly recommend it as it gives your rhetoric an authentic confidence. Write only what commands their full attention, and unless you're a mathematician, leave the crooked explanations to the 'parenthesissies.'