Absolutely nothing to do with accuracy.
Battlefield is not Counterstrike or Lol of Duty. It's positioned between esports retardedness titles and simulation.
If I want to play competitive FPS I will pick a suitable title, Quake, CS or otherwise. Battlefield is not one of these titles, it never will be (Bloody never well should be either). I play Battlefield because of the way it positions itself. If I hit someone centre mass or in the head with more than 1 bullet they are dead. It will take more if I shoot them in the arms or legs. I am still rewarded with quicker kills for well placed shots but not penalised with super unrealistic BS that is someone running off to regen health despite me putting 3 in the centre mass and them still running about freely.
No BF3 is not a full on sim and plenty is unrealistic, it's a compromise. Normal is a compromise too far. Nothing to do with not needing to aim more accurately (You damn well do as you are rewarded for it) and everything to do with not having to put up with BS that normal brings.
Yet again though, the 'Pro' players come out of the woodwork and preach aiming accuracy as the be all and end all of skill, in which case remove every vehicle, remove every utility (C4, claymores, MAVs, TUGS, mortar, smoke), remove any custom-ability or disparity between weapons that affects aim and..oh wait - No longer Battlefield are we?