A fifteen-gun Bayern and the volume of fire

How much improvement would fifteen 13.8-inch guns give a Bayern-type ship?

The answer emphasizes a large increase in broadside volume, illustrated by thirty rounds per minute if each gun fires twice.

Fifteen 13.8-inch guns would give the hypothetical Bayern a much heavier broadside than the preceding 12-inch-gun ships. The answer still distinguishes that battery from adopting 15-inch weapons. Its illustration assumes two rounds per gun per minute, producing thirty rounds per minute across the battery. The rapid sequence of shells is the point of the comparison, rather than a claim that each shell has the effect of a larger-calibre hit.