Reading here about Breaking the Ice makes me wonder whether some Narratavist features (in this, or other similar games) are actually expressions of Simulation of Relationships. If you roll dice and compare to a trait for "Likeability" (or "Humanity" or whatever -- I'm trying to make this more widely applicable) aren't you veering towards Sim?
Welcome to the Forge, jaw6! Please disclose your name in your sig. I feel silly refering to you by your username:)
You're going to get a handful of helpful responses to this question. I want to point out that particular types of mechanics, while they may be more or less well-suited to support a particular agenda, are not, of themselves, definite indicators. Narrativist play is entirely possible to support by systems that use rolled dice compared against number-rated traits. (TSOY, for example.)
Ah, thanks. Hopefully, my sig will be working now?
This is kinda an interesting question.
If we're making generalizations, in regard to relationship mechanics & whatnot, I think the difference between Sim and Nar games is that Nar-facilitating games tend to present relationships as a means for generating conflict. This is certainly the case with my own game, The Mountain Witch.
Sim games on the other hand often present relationships simply because "that's the way it is/should be". In other words, relationships in Sim games aren't intended to generate Conflict (unless its some sort of genre convention, like how Scully is always getting captured in X-Files).
When players start using relationship mechanics to generate conflict, that's a good sign that the players are drifting from Sim to Nar.