After a brief discussion with a SG about the InMe guidelines since resolved, I thought I'd put the discussion out here just to see what others thought.
InMe guidelines from the main book list that Momentary spells only ask 1 question.
InMe15 allows you to ask one question of your target.
InMe20 allows you to know what someone did yesterday.
InMe25 gives you all the information you wish from a target's mind.
What happens when you cast based on the InMe15 guideline and ask, "what did you do yesterday" as your question? Doesn't this obviate the InMe20 guideline?
How does "Peering into the Mortal Mind" work, in that its a Momentary InMe25 spell that appears to give you a heck of a lot more than 1 question with its Momentary duration?
Yes, that pretty much works. However, I would think you would get the equivalent of a one to few sentence answer instead of the picture-book that you would get with the higher guideline. At least, that's how I'd play it.
I don't think it does, I think the guideline makes the question bigger. Instead of "What do you know about X?" it has become "What do you know?" or at least along those lines, making the answer much bigger.
The base 20 guideline allows you to know what the target did yesterday in a very detailed way (= everything that the target remembers), whether if you use the base 15 guideline and ask "what did you do yesterday ?" you will get a vague answer like "I was in my lab working on spell X" without further details.