You know what the absolutely craziest thing is...? This "bug" didn't exist on my old ATi card, so I guess it's something to do with how the new card (and I'm willing to bet, nVidia cards) handles shaders. By the gods, I think the only thing we upgrade nowadays is problems!
ETA: All my tests were conducted in a Single Mission I created. Just my boat and a stationary Huge Passenger Liner for me to shoot at.