Tried something similar to it with a fiction book. I PR it, and didn't activate it. I then went to take a nap (polyphasic sleep experimenter), and imagined what the book was about. Kinda like a combo of imagestreaming/conscious dreaming. I was awake...
Anyhow, I later rapid read the book and my plot/specific instance from the dream/IS was absolutely correct. Felt like I was rereading the book. Also, I knew who did it (was a mystery).
I have done about 7hours of IS'ing, but then I have taken a week's break.
This has been really exciting--PR'ing really, really works!