I don't see why a game has to put gameplay before story. Why? Because it might not be fun?

Because it might become like a movie (non-interactive)?

[Stuff about novels and comic books and Schafer games]
I didn't understand your point about novels and comic books, and I haven't played Schafer games, so all of this argument is going over my head.
Also, you again said that any book or movie has better writing than any video game. It's literally right there at the beginning of your post. That statement is completely ridiculous and you have no evidence to back up the claim. "I stated that a game should not strive to be a movie (or a book, but good luck finding writers of that calibre in the video game industry)" Really?
Yes, really. (Let's not derail the thread, but) I am stating absolutely that no video game has yet produced a Citizen Kane, a Macbeth, a Leon, a Sputnik Sweetheart, a Lolita, a Count of Monte Cristo, a Gone with the Wind, a Casablanca, or even something like A Game of Thrones.
Would it really be so bad if in Dishonored they sacrificed the gameplay to enhance the narrative, and then by a result enhanced the overall experience?
^ You're skirting very close to begging the question, here. ^
A great example of this is Alan Wake, which sacrifices gameplay in order to tell a better story, which resulted in the player being further immersed in its world and characters.
I've played Alan Wake, but I didn't get the impression that it does this. How does it sacrifice gameplay to tell a better story?
The story themselves and the way they are structured is what needs to move away from being cinematic (I'm against that right now because in the mainstream that's choking originality and experimentation to death right now), but not cutscenes. It seems completely arbitrary to shut off cutscenes and cinematic tools that video games can use.
This is why I don't like cutscenes. Just like any tool, they're fine when they're used judiciously and appropriately, but at the moment they're a crutch, because the proper mindset mostly isn't there. Shadow of the Colossus, for instance, only used cutscenes when absolutely necessary, and in ways that made sense for the narrative that had already been established. That's fine. But don't take control away from the player and make the character do things that don't make sense for that character from an in-game perspective, and/or that the player can perfectly well do himself in-game. E.g. don't show me a cinematic of my FPS dude shooting things -- that's what I'm there to do.
I guess the point I'm trying to make in a not so clear way is that defining something as a certain category (movie, book, video game, etc.) and saying that they have to stay within the parameters of the category is silly.
I'm not saying that they have to stay in particular categories, but I am saying that the more you move away from one medium to another, the more the overall experience tends to suffer, because very (very) few people are good at that balancing act. Look at the clicky visual novel. Does that offer a good gameplay experience? No. And from the one or two I've read, they offer absolutely atrocious story.
Particular mediums have become mainstream because they're particularly good at what they do. When you try to mix the two or more of them, 99.9% of the time, you end up with drek.
How did we get here, again?
Right, the Outsider. And the plot of Dishonored. Look, vengeance as the driving force behind narrative is nothing new to video games, but I think there are enough twists and points of difference (like the supernatural puppeteer that is the Outsider) that it might be interesting nonetheless. And maybe I'm wrong. Maybe this is the first game that will ever have been created that is able to go toe-to-toe with the stories that books and cinema have told.
