Commas break up clauses (whatever those are). Commas separate ideas by introducing a momentary pause, either mental or aloud, but don’t signal the start of a completely new idea the way a period or line break does.
In poetry, commas…I don’t know enough about commas in poetry to say anything there. I always thought they were like line breaks for the middle of lines.
My writing grows increasingly succinct. I used to be a long-winded person prone to lots of parallel construction, clauses and clauses strung together by commas and hyperbole.
I have no idea what happened. Is this the loss of a style because all the writing I had to do most recently required succinctness? Did I just get older and actually develop my own style, instead of cribbing from my favorite authors?
And what the hell are commas for, anyway?