A year back when H2H was still around I found that everyone was getting shot at by the AA. I simply didn't see the AA firing at others around me.
edit: its completely different from the field ack model - that just targets the nearest plane to each gun, looks like its delayed but thats just the guns turning to target. I suspect this is the problem with the puffy model - if 5" did the same they would spend all their time acquiring new targets and not firing.