Interesting, thanks @Quix for the diggin' on that. I'll have to check what I've read in the past. I remember reading about the letter, but not with the details given here.
You're welcome.
You likely know it's not my style to dig that deep that often to verify something. LOL.
I tend to rely on 70 years of extensive reading and my gut . . . and given my tendencies, that means I fall prey to a percentage of false positives.
Yet, the naysayers seem wedded to false negatives, imho. LOL. So maybe we provide some balance for one another occasionally.
But that one has always bugged me--assuming it was true so many decades because my military buddies insisted it was . . . it bugged me that people could be so heartless . . . and then the 'debunking' narrative . . . so I had to check it out to deal with it niggling at me. LOL.