You're saying mouse acceleration simulates real life aiming? I don't agree, this is like handicaping people who can actually track and aim.
Modern guns are not so heavy, for example AK-107 is around 3.5 kg, and you are saying trained soldier would have problems moving 3.5 kg when aiming which would cause him to aim slower? Of course not. Main problem is that you're gaining too much speed when moving mouse faster, which is NOT realistic.
Please BI, remove this or at least put an option to turn it off in your next patch.