I was under the impression that SoA never really tried. What was the point, after all? Their lands suck, and they were completely ineffective. The only time they ever managed to do anything was when Sirion marched up the peninsula and held their hands to escort them around a few regions.
As far as I know, SoA never launched any major offensive campaigns against OI. Sure, they attacked Kazan and Stora a few times... But that's because OI was being a pest, not because they were out to kill them.
That being said, OI isn't what it used to be. It is stronger than it was. Granted, I think they would still have to do some land shifting and noble gaining before they could be a middle of the pack realm, but their forces(if organized well) can tip the balance of war now, whereas against Sirion, they were practically a token force waiting to get squashed.