From my understanding, a core tenet is to "put the story/premise you’re addressing first; treat rules as tools."
In fact, I've gathered that one could simply ignore a rule entirely if a player were, for instance, to be momentarily enraptured in a particularly eloquent bit of roleplaying, creating "good stuff," so to speak. I see narrativism as encouraging them to continue spinning the yarn and building the story even if it meant ignoring a rule they'd otherwise be subject to but one that would break the player's flow.
Isn't that basically the same as the DM deferring to a player to continue roleplaying because they've got a good thing going?