Well, in a sense. It is based mostly on taking a dramatic need of a character (in many cases, it could also be some other conceit/theme) and 'boiling it'. Every time the player narrates an action the game takes that, or its intent, and runs it through some sort of process which produces something, blowback, progress, setbacks, complications, something. That 'something' generally propels things forward into a new situation which is more urgent in some sense. The AIM is to examine the need/conceit and drive play forward. It COULD be dramatic in outcome, or not. Just like an OD&D dungeon crawl will present challenges and MAY produce some sort of narrative of daring-do, or it might just describe how the PCs opened the door to the first room and were instantly stung to death by giant wasps... Most of us are not good enough players or GMs to produce really excellent dramatic narratives out of SN play, and I don't really consciously aim for that. I just try to make each new scene evoke some sort of "Oh my gosh! What now!!!???"