"Well I couldn't do much worse !"

A very dangerous boast, my friend.
Got a lot of experience of the art and science of submarining, have you?
Often, things that seem simple turn out to be just the opposite.
As one who's spent a fair bit of time at sea, I have nothing but respect for men and women who risk their lives in the service of the nation, and especially in what's probably the most dangerous branch of Naval operations.