The MAnual of Divinity II says about Mindreading:
"...some minds are stronger than others and so, more XP needed to read it ..!"
So, when Mindreading costs for example 1 or 33 XP, it also CAN possible a very good thing!
And in Farglow you can do a quest for the shopkeeper ..I forgot his name, but he read gladly many books (hint hint

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I mindread most of al NPC's!