Something to throw in here, having been both the gunner and the gunned-down: with lots of the larger fleet groups around, there's a potential for what, 10-14 of the 5" guns hammering away? Unless I'm totally off, 2 dual batteries and 2 singles on the carrier, 2 duals on (both of) the cruisers... That's a helluva lot of lead being thrown around. While I don't personally think its that easy to pick a plane out of a furball, its certainly possible to hammer away for 10 mins and get quite a few.
However, on the other side of this coin, its still relatively easy to come shreaking down with a form of buffs or come in with some heavy fighters and sink the boat (unless the gunners happen to be very lucky or very good). Until such time as that can be prevented, or at least made much more difficult, you can't, IMHO, put enough guns on the boats. I'm thinking the murderous 5" guns are a necessary evil.
Cheers,
hub