It would be nice if we could play back the dialogues related to the quests, but...
In general, yes. You're binding the book, and making the ink as an alchemist. The arcanist is the one who fills it, as that's not your bag, baby. Why would the alchemist know an arcanist's arcanima better than the arcanist?
The ink, being made of precious metal, facilitates the flow of aether. This is also seen with goldsmithing in the making of thaumaturge scepters and staves, as well as weaving in the making of certain clothes.
The books, themselves, are made of wood, leather, and precious metals. All of these things also facilitate the flow of aether.