When I used the game's default AA option, I could see ghosting on the character edges. It was most visible when aiming up at the sky and moving around. However, disabling the game's AA and using this fix seems to have stopped this issue. If this can be shown to help on other systems too it could be noted as being a fix.
My system can't handle both options set to 4x, so I tried 2x and it seems to work ok.