^^^The only work of Whedon's I'm familiar with is one Alien movie; the Buffy movie; one episode of the Buffy series; maybe seven episodes of Firefly; the Serenity movie; about three episodes of Dollhouse, and Dr. Horrible's Sing-Along Blog. Loved Dr. Horrible, (maybe that's because I'm a sucker for musicals with real plots) but I don't think the rest of it constitutes a notably good body of work.
Still, it is obvious that I haven't seen enough of the years of episodes of Buffy the series and years of episodes of Angel to be so familiar with Whedonesque tropes. And I'm sure that there are many people in the same position as me. But I can easily imagine that those who are familiar with all those hours of Whedon can find Cabin in the Woods rather familiar, not novel nor clever. For instance, the plot hinges on a character inexplicably but fortuitously returning from apparent death. This is a moss-covered plot device save for the twist that the character who returns is not the villain, but the hero. (If you can call someone whose actions doom humanity the hero, except that the movie plainly deems him the hero.) Look, a plot hole in an unusual shape! Clever, yes, but not as clever as writing a plot without holes.
Whedon and his co-writer weren't just winking at us, they were giving us the finger too. Why not? Why do
we want to see the slut get killed?