Linking back to my previous post, this is exactly why I tend to belive IS simply isn't following the original character lore. Koei Tecmo is more than capable of writing such intricate callbacks. And trust me, they do this constantly in their own games as well. The difference in attitude is obvious.
Sylvain is such an interesting character. In his C-support with Dimitri, he mentions that he tries to avoid Dimitri because Dimitri often stays up late. Then, in the Verdant Wind route, his line when he falls at Gronder Field is: 'Your Highness, you won't have any more nightmares, will you?