Let's do an experiment. The next time you're out in public, try sneaking up on a stranger with a backpack of clinking bottles, cans of nails, and ammo, and see how far you get before the cops get involved. Our guess? Not that far--which is why Joel's "stealth" skills in the Last of Us appear to rely less on his ability to silently take down his enemies, and more on those enemies being either mute, deaf, or both.
We're not picking on The Last of Us' AI (at least, not yet). In fact, on higher difficulties, those clickers and hunters can be supernaturally effective at tracking us by the smallest sounds. What we are picking on is the fact that none of Joel's enemies seem to clue in to the fact their buddies are getting violently choked out just a few feet away, or that clickers have exceptional hearing except for when runners are getting their faces smashed into the wall behind their back. There were too many times when we were sure our cover had been blown by a noisy takedown, only to breath a sigh of relief when nearby foes seemed oblivious to the carnage going around them. We guess we're thankful, but it sometimes made all that sneaking around feel silly.