A video for Uncharted 3 showed just how unbalanced the multiplayer is (in a fairly satirical fashion). If you haven’t played Uncharted, think about how bad aiming was in Splinter Cell’s original release on the PS2 when you were being shot at after Sam blew his cover, yeah, it’s a bit better than that as someone shooting blindly can obliterate you in mere moments.
Vid below, contains large amounts of crude language.
The video shows easily that outright running and gunning quite literally makes aiming completely useless in most situations. If you’re missing the point, being able to run and gun gives a far more brutal spray in close quarters as you can effortlessly turn around and aim at the targets far faster than they can turn around while aiming. Rather shoddy work on Naughty Dog’s part, but the multiplayer of Uncharted doesn’t have many good reviews as far as I’m aware.
Regardless, Naughty Dog have stated that they want the multiplayer aspect to be mindless fun instead of huge amounts of strategy and metagame dominating the skill levels. This might get nerfed or remedied in a later release since this is clearly a very broken strategy. They also patched issues in the summer beta within a day or two when it became a noticeable problem.
Or you could just become better at keeping track of who the freeshooter run and gunners are, lob a grenade at your feet and get the hell out of there so they quite literally walk straight into it. Besides, why are you letting someone get into your face in the middle of a gunfight? You might as well let them shoot you.
I found the video quite hilarious really, but it does highlight how much a broken tactic can change things.