Usage dictates and all that, so we need to be on the same page to effectively discuss. But the definition of linear storytelling that would make the plot coupons "linear" would essentially make for a very limited 1% style of storytelling that wasn't. And that's just counterintuitive.
Plot coupons does seem like a cheap cop-out though, as does the storyline missions vs. fluffy filler missions structure of mass effect. I mean, I know what they were trying to do when they set up a sci-fi epic, so they can't really be judged strictly on "it wasn't non-linear enough." There will always be a place for stories told from authoritative voice; to say that Star Wars would only be worthwhile if the user got to direct how things went down is asinine. To say that GTA has no good story since it wasn't mission one to mission two, gangland epic, the next Godfather - that's missing the point too.
Signatures=pretense. And I'm far too well read for that. :D