Something feels wrong.. mistranslation?
MC earns experience writing in the book. To gain something from the book, like the past experiences/written story of "mad quack", he has to spend earned experience points. So why does MC suddenly "earn" 10000 experience points learning more experiences of "mad quack" ?
About changing the scribe, what would be the point? The book does not tell any names of past owners, thus changing who gave those "mad quack" experiences seems pointless. This is confused by saying
consumption for acquiring
aka "earning" experience points will be twice as hard, and the introduction of "your power", which is possession of original scribe (possible?) into MCs body. MC clearly thinks this is a bad idea, but says