The 76 mm gun is assigned a different role from the close-in gun used as the last defensive layer. It can put a fragmentation barrier farther from the ship. In an illustrative four-missile attack, a barrage that stops two leaves only two for the remaining close-in weapons and spoofing measures. That example explains the value of stacking imperfect defences. It is not a measured interception rate or a promise of complete protection.
Notable Point · 3:42:06-3:43:41
How a fragmentation layer reduces the load on close-in defences
A 76 mm fragmentation barrage is presented as an extra layer that can reduce the number of missiles reaching close-in weapons and decoys.