I've only read half of the second book because of the lack of time but I do agree with you both on what the writing feels like and what will happen if loops are introduced. There are already fans discussing of th Blood Raven being old Bran coming from another timeline where the world was destroyed.

Yeah. It just causes a closed causal loop. Hodor has to be witless for him to become witless. So there is no "true" explanation for his handicap.