One of the things only true Bible nerds care about is composition history. Composition history, as the name suggests, is the study of how the biblical texts came to be written. For the average Christian it seems quite simple but it is actually a complicated issue and a lot of scholarly ink has been spilt over it. As with many academic matters the ordinary Christian is not concerned about them. Even though debates about composition can get incredibly technical and sometimes steeped in a lot of conjecture and educated guess work, I still think it matters for how the ordinary believer reads the Bible, even if they are unaware of all the details.