There’s this standing cliche of soldiers writing down their Final Thoughts in a letter and handing it off to a buddy.
That seems terrifically inefficient, has any military formalized the sending on of the Last Words of a service person?
According to Ken Burns’ The Civil War soldiers would often pin their letters to the back of their uniforms in case they were struck down and killed in battle. Usually (though occasionally not) the fallen soldiers bodies would be gathered for burial and the letters delivered then, sometimes even by enemy forces.
As far as modern times goes, I assume the military just gathers all outgoing mail on a regular schedule. It’s merely up to the soldier if they want to write a letter before a significant battle.
But that is the exact opposite of the OP’s scenario , which is that the soldier does not want his letter sent, unless he dies.
I assume you would give it to your buddy and ask them to mail it if you were killed in action.
I would leave it with my stuff. I believe that an officer goes through your stuff before it is returned to next of kin, to be sure that they don’t sent your dirty magazines home to your Mom.
Yeah, that’s the cliché the OP spoke of :
A) it’s inefficient
B) what if your buddy gets killed/killed too?
In the Dambusters film, the crews left letters in their quarters.