Having multiple options for how to offset parenthetical asides, far from being redundant (or even confusing), offers us—as writers and readers—more opportunities to express the tonal variations (or nuances) that we would – in spoken language – communicate through our voice and body language; moreover it lets us vary the visual, aesthetic quality of our prose – which is as much a part of the experience of reading as comprehension is.

Is this a written excerpt from a text book or something? This single sentence makes more sense than many of the arguments I've seen previously.

Nah, it’s just a deliberate hodge-podge of a sentence where I threw in every subclause I could to try to illustrate the point.