This article is about an interesting story how ambiguous cryptographic padding lead to the delay of reinforcements during the Pacific War at the height of the Battle of Leyte Gulf on October 25, 1944.

"For historians and World War II buffs alike, the phrase “THE WORLD WONDERS” — from one of millions of U.S. Navy radio messages — is a fabled part of the lore of the Pacific war. With perhaps the exception of the electrifying “AIR RAID PEARL HARBOR X THIS IS NO DRILL” dispatch sent by Commander Logan C. Ramsey at the beginning of the Japanese attack on 7 December 1941, “THE WORLD WONDERS” is the best-known message of the entire war, but unlike Ramsey’s radio broadcast, it is embroiled in controversy. No account of the epic Battle of Leyte Gulf can neglect the message and its consequences."

Abstract of the story:
When Nimitz, at CINCPAC headquarters in Hawaii, saw Kinkaid's plea for help he sent a message to Halsey, simply asking for the current location of Task Force 34, which due to a previous misunderstanding, was unclear:
Where is, repeat, where is Task Force Thirty Four?
With the addition of metadata including routing and classification information, as well as the padding at the head and tail, the entire plaintext message to be encoded and transmitted to Halsey was:
TURKEY TROTS TO WATER GG FROM CINCPAC ACTION COM THIRD FLEET INFO COMINCH CTF SEVENTY-SEVEN X WHERE IS RPT WHERE IS TASK FORCE THIRTY FOUR RR THE WORLD WONDERS
U.S. Navy procedure called for the padding to be added to the start and end of the message, which were vulnerable to cryptanalysis due to the use of common phrases and words (such as "Yours sincerely") in those sections. The words chosen for padding should have been obviously irrelevant to the actual message, however Nimitz's enciphering clerk used a phrase that "[just] popped into my head". Historians note similarity to Lord Tennyson's poem "The Charge of the Light Brigade" about the eponymous battle, which was also fought on October 25 (of 1854), as the poem twice contains the phrase "All the world wonder’d".
While decrypting and transcribing the message, Halsey's radio officer properly removed the leading phrase, but the trailing phrase looked appropriate and he seems to have thought it was intended and so left it in before passing it on to Halsey, who read it as:
Where is, repeat, where is Task Force Thirty Four? The world wonders._
The structure tagging (the 'RR's) should have made clear that the phrase was in fact padding. In all the ships and stations that received the message, only the decoder on Halsey's flagship, USS New Jersey, failed to delete both padding phrases.
Fascinating illustration of the difficulty of carrying cryptography over human communication. As is famous, in Bletchley Park, "cribs" were key to cracking Enigma messages, so it's not surprising that in '44 the Americans were keenly aware of the need to not use guessable starts and ends to messages, but using properly random padding is super hard for a human to transfer over a radio.
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In artillery, "repeat" means "fire again". So the phrase, "Say again, over." is used to clearly request that the RTO (radio telephone operator) did not fully understand the phrase.
So repeat is never used except to have FDC Fire Direction Control "repeat" the same volley of artillery, naval gun, mortar or missile fire. Hence in class when we would fuck up and say, "repeat" the instructor would say, "shot over". Letting us know that munitions were coming again and we might be getting killed.
Just my two cannons worth of knowledge.
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Thanks for your comment, I find all this military stuff really interesting since it's very serious stuff so they most likely always have good reasons (like not getting killed or killing your friends) for why they do what they do.
This reminded me of this scene (even though it's not about using "repeat" in the wrong context) https://www.youtube.com/watch?v=B9xg2-6JDL8
and about a section in the book Chickenhawk where the protagonist (Huey transport pilot) is at a artillery site and realizes how everyone is basically fighting their own war.
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