Summary pretty well states it. Issue only arises when absolutely no writing has been done in the book, i.e, it has no NBT tag. This might affect normal players when, for example, they already have an idea with what they want to do with their Book and Quill and so name it right after crafting it.

To reproduce:
1. Get or craft Book and Quill.
2. Name Book and Quill in anvil.
3. Attempt to write in it.