I can see why you could lose a ship in the yards. More flammables, zero watertight integrity or ability set boundaries, reduced Manning, firemains and foam stations tagged out, etc. We had a yardbirds storing hazmat fire nearly get away from us on CVN 71. Right next to where 12’x12’ holes were cut from flight deck to the bottom in order to pull the rudder pins. Good luck setting boundaries on that one.
The yards were a terrible place to have a fire. I did a yard period with the Forrestal. You are right, cables through the hatches, tons of welding going on. Fire hoses being replaced. I don't remember the boat (Maybe the Saratoga) was in the yards with us and they had a pretty good fire, we sent quite a few people to her to help them fight and contain the fire.
Worse yet was civilian boats, I was part of the Underway Rescue and Assistance Detail. We did a couple of assists with civilian ships mid ocean, those guys knew next to nothing about fire fighting. If the fire suppression system didn't take care of it they were ready to abandon their ship.
Fun times. Fight the fire, dewater the boat and hopefully send them on their way.
bob