A BB is always going to be was always a General Support Ship when it came to NGF support, especially her main batteries the 16' 50's. The Iowa Class wagons were always pretty stingy with the 16" rounds and if the were firing NGF missions preferred to use the secondary batteries of 5" 38's. If the target could be ranged by the 5 inchers. Even then the BB had to be released by the CATF or higher to provide direct support missions.
There had to be a reason to get one of the big girls to fire in direct support, such as the direct support ship (generally a DD or FF) being off station, at the far end of a track or having gun mount casualty problems. The need always had to be pressing for the GS BB to be released to a DS role.
Even then requesting of main battery fire by the SFCP or the SALT team was generally ignored by combat control if the target could be ranged with secondary battery guns.
Jersey's missions in Beirut when she employed her main battery were at targets that could not be ranged by ethier the Marine Artillery or by DS vessels or were considered high value targets by the command authority.
I spoke with an Officer who directed NGF in Beirut and he said that in all the fire missions he fired he received the main battery only once when he IDed an active Druze rocket site. He said that the 16 Inch rounds "Just freakin (censored and changed) took the whole freakin moutain side down. It was sooooo freakin cool." all his other missions were of the 5 inch variety. Although he did say he heard Jersey and saw Jesey hitting targets in the Bekka Valley and other inland areas, those missions were pre plots and not observed missions.
Another short fall of the 16 inch gun is it's limited projectile menu. Pretty much APC, Armor Piercing anti ship rounds and HC , High Capacity, the NGF version of HE quick for shore bombardment. Your fuze setting and fuze selection are pretty much nil, it's all Fuze Quick for the most part.
5 inch guns on the other hand offer a much better selection, especially for a manuver element needing direct support. From HE quick to Variable Time and Mechanical time, Smoke and Illum etc, the 5 inch is a much more versitile platform and has much faster rate of fire and adjustment.
So IMO while the 16 inch may have a place in pre assault bombardment and the ability to reach farther inland in the intial stages of an assault, given the advent Cruise Missles and Air Power's enhanced effectiveness the 16 inch gun has pretty much lived out it's day.