H&D2 does indeed suffer from odd AI quirks, but nothing near the hellish torture that was H&D1, which I absolutely loved when it came out. Loved 2 even more. The omniscient enemies are now gone, so no more getting pegged by the invisible guy a mile away. I don't recall an enemy ever unrealistically seeing me. In my opinion, it fixed most of the problems, or at least improved them, from the first one and made a few new ones, as is often the case with sequels and such. But by and large, H&D2 (in my opinion) is an excelent game that I had no trouble with looking past its flaws. Or maybe I'm just a sucker for bitch-slapping Nazis. Again.
And again.