"So,my Simmons really IS a POS,it's just that I'm too dumb to realize it?"
No, you know what you have. But, do you realize how lucky you have been...so far?
I have a buddy who bought a 6-18x Atec for his Ruger 17 HMR, against my advice. That's NOT a heavy recoiler! It shot well and he was greatly pleased for some three years but then his groups started growing. He fought bore cleaning, bedding, mount/ring screws for a year but the groups kept growing, eventually to about 6 MOA. I loaned him an an old Weaver 10x and his groups immediately went back to sub-MOA. And, even when it worked, the barrel distortion was bad, especially strong around the edges.
Have seen exactly the same thing to some degree in every BSA I've been exposed to.