Pretty good analysis. You forgot the part where the porting directs the sound wave back at the shooters ears. And, the part about the mess that is created in the ports themselves, that is a pain in the butt to clean out.

My dad, thought it was the cat’s meow, on everything. I beg to differ. My first “ported” gun had a vented Cutts Compensator on it, I couldn’t wait to get the damn thing removed. It patterned fine, but, made a racket that everybody hated. The interchangeable chokes were a great idea, the vents, not so much.

Best,
Ted