Proof or sources please.
Glenn Miller's music was designed to dishearten the Wermacht?
Gosh, the things one learns in one's old age. As I recall, the Ship's Service jukeboxes played Glenn Miller all day long. I guess we didn't know it was designed to subvert the German General Command and all its troops.
By the way, does one have to play those old 78's backwards to get the disheartening message? Come to think of it, never once did I ever hear Miller's 78's being played backwards.
But live and learn, I suppose.