Originally Posted by Happy Jack
Think about how much harder it would be if Ellie or anyone other than Joel could alert enemies. Count your blessings, it's only a limitation of the technology.
Oh man, there is nothing I hate worse than dumb AI that ends up getting me killed. I'd much rather suspend disbelief and let the characters interact/travel with me without getting caught 99% of the time. I thought ND had a fairly decent balance with it.