They aren't deliberate "cheat modes", they're hacks. Certain types of hacks are extremely difficult to prevent or even detect. There was an article on HN a few

They aren't deliberate "cheat modes", they're hacks. Certain types of hacks are extremely difficult to prevent or even detect. There was an article on HN a few months ago (can't find it right now) that discussed hooking into the GPU to avoid detection.