You don't really memorize babble. If a baby babbles, and then 3 dayslater another baby babbles in a similar way, it's not like you'll draw a connection. In all likelyhood Parshendi are dawnchanting, but nobody's ever noticed or connected it. Written babble is hard to connect to spoken babble, and obscure generals nobody has heard babble is hard to connect to rarely-paid-attention to babble.
Did any of that make sense?