> It's not training on books, but it will answer questions about the book you're reading. Doesn't pass the sniff test.

What do you mean? Presumably the implication is that it will essentially read the book (or search through it) in order to answer questions about it. An LLM can of course summarize text that's not in its training set.

"Reads the book" is the issue, yes. It's possible they aren't training. Vit to be frank, we're long past the BOTD where tech companies aren't going to attempt to traon on every little thing fed into their servers.

Happy to be proven wrong, though.