The back blast from one of the 16’s would blow everyone on the deck overboard.
There is no back last with a 16” gun. Shock waves and concussion are more than enough to cause serious bodily or death.
Nope. In this video the camera men are standing on deck next to the guns firing. At the 3:28 mark in the video.
https://www.youtube.com/watch?v=-5ATYPrZnSQ