I think narrativism is bullshit when used with traditional techniques. This is common but I just Do Not Want. I don't have any problems with a game like Fiasco or Nerver av stål or Microscope. When those kinds of games appeared I thought they were cool.
Playing "Pathfinder with bangs" I think is bull. Adding bangs to a traditional game—and I'd argue that's what Sorcerer does/is—is something that does not sit well with me.
To me the pre-writing / frustrated author GMing style (story "before": gnusto) works best with a game set up around it (like Chuubo's if you want the players to write stories [which is cool], or something like Dread or some shit like that if you want the GM to write stories) and the story NOW (nitfol) goal works best with a game using completely alien & non-traditional techniques.
And by "works best" I don't mean more effective. Not at all. What I do mean is that it's least likely to undermine the glory of blorb and the blorbiness of the gloracle.
Let me try another way: no-one is going to think the GM is railroading you in Microscope (also, there is no GM).
So I'm not saying that most narrativist games are using alien techniques. I am saying that story games that use alien techniques (typically but not necessarily GM-less being one of those techniques) are less threatening to me as a devotee of blorb.
With that said, finding which nitfol techniques work well with blorb without undermining it can enhance a blorb game a lot. There's nothing wrong with giving a couple of opportunities for Addressing some Premise in the sandbox as long as it doesn't come at the expense of the sandbox. It's actually a really nice mix.
The trick to doing two things at once is to decide which of the things matter the most to you and accept that the other thing is compromised. For example, putting mittens on while running down the stairs requires me to keep stair running in my mind in a way that I wouldn't have to do if I wasn't also putting mittens on. Just running down the stairs I don't have to think at all, the body just does it automatically. But also putting mittens, I have to be accepting of the fact that there's an occasional gap or fumble in the mittens-pulling-on because I sure as heckfire don't want there to be one in the stairs-down-running.
And I don't want there to be a compromise in the integrity of blorb.
So for me a super weird & alien game like Fiasco, Microscope, the Skeletons… they stay so far away from blorb (no risk of falling in stairs) so I feel safe with them. A game like Sorcerer on the other hand is like "nooo you're gonna trip & hurt yourself!".
Unless you take care and move all bang-like-stuff through the "sandboxifying queue" that is rolltables & map keys, make them less scripted and more part of the organic world (handing responsibility of introducing them over to the gloracle)—and make them something that the hobos might miss or that maybe don't happen. An example of a fail is in my beloved Lost Mine of Phandelver which is almost the perfect adventure but there is one room where someone is "juuuust about to get killed when the hobos arrive" — rereading the adventure right now, the room description looks innocuous and not "time-sensitive" (the guy is just beaten up & is being interrogated) but my players somehow got the impression that the moment was "scripted" and it wasn't well received therefore. "Deep Carbon Observatory" has this problem too, which is unfair to it; the event generator system for the very first part flows SO naturally into each other, and the choices the players make are so seamlessly integrated, that it feels completely scripted and that there were never any choices in the first place, making it feel like a completely railroaded & therefore crappy sequence. So those are some pitfalls you have to watch out for when working with the bane of all sandbox: "events".
The random rumor table is a very valuable tool to place things like this on.