Seems you have some Linguistic Education.....100% than I do anyway.
I wish I had the link, but alas, I do not.
Concerns a "guy" with a letter from his Grandfather to his (the "guy") Grandmother.
Was written during WWII. The Grandfather was a German soldier.
This guy (I think) spoke German, but he said he could not read his Grandfathers letter, because it was written in some type of German that quickly faded after WWII.
Does this sound "right" to you.?
Did the German Language go through a big change...post WWII.?
Thank You
BTW...one of the best people in the world (Noam Chomsky) is a linguist.