The problem isn't the means, it's the execution. They already do have plenty of books in circulation. Some out here are arguing that the books should be enough or that the players should research who Shar is on their own.
The other side of it is that some think that there should be some cutscene or something that explains who Shar is, at least giving some basic knowledge and information to the player so when Shadowheart does her "big reveal" the player isn't wondering, "Shar who?"
