I mean, isn't all AI in games limited by design? What's the issue with that?
"Designers instructed us not to improve [the AI] in certain ways, because they believed that players enjoyed being able to dominate the AI and that we shouldn’t deprive them of that.”
This is true. Wait what? What's the issue? If you make the AI un-defeatable then players won't have fun. I can see where some limitations may be annoying to very advanced players, but most normal players typically struggle vs AI in strategy games at high difficulty settings. This is where Age of Empires 2s latest settings that include tunable options for AI are the ultimate way to handle AI. But the AI being limited by design isn't really a problem IMO.