[DoodleDawg]

To the contrary! Visually, it is very, very easy to see those high-contrast white-deckhouses on cargo ships many miles off through a periscope. Same from a low-flying aircraft. Light “haze grey” with NO contrasting colors - they need to paint out the black smokestacks too! - is very valuable in protecting a ship against submarine attack.

If all you have is your periscope. But the submarine sonar will track the ship miles before it gets into visual range and can target it without even using visual identification.

[Robert A Cook PE]

You might think so.

But, of two merchants and a destroyer and a carrier and an amphib, all 20 miles off but close to each other near the shore, how do you aim a torpedo at the right target?