The Joy and Danger of the Rule of Cool

I mentioned the Rule of Cool at the end of my last entry, and I want to discuss it a bit more today.  While the TV Tropes page defines the rule well enough, I'd like talk about how it pertains to plotting and writing a story.  To quote:

''The Cool Stuff Theory of Literature is as follows: All literature consists of whatever the writer thinks is cool. The reader will like the book to the degree that he agrees with the writer about what's cool. And that works all the way from the external trappings to the level of metaphor, subtext, and the way one uses words. In other words, I happen not to think that full-plate armor and great big honking greatswords are cool. I don't like 'em. I like cloaks and rapiers. So I write stories with a lot of cloaks and rapiers in 'em, 'cause that's cool. Guys who like military hardware, who think advanced military hardware is cool, are not gonna jump all over my books, because they have other ideas about what's cool.

The novel should be understood as a structure built to accommodate the greatest possible amount of cool stuff.  — Steven Brust

It's that last line that leads to all the trouble.

The Rule of Cool is very, very, very easy to follow when writing: throw in everything you think would make your work awesome.  I'm fully convinced the ending sequence of Jim Butcher's Dead Beat was done purely because Mr. Butcher thought of Harry Dresden riding a zombie tyrannosaurus rex through the streets of Chicago and worked backward to make sure the scene made sense in the context of the story.  If the scene had just kind of happened, it would still have been awesome, but it would have felt tacked on for the sake of awesomeness.

And that's where the problem lies.  It's way too easy to think "that would be cool, that should happen" and put something into a story without considering whether it truly works or not.  In my last entry, I talked about a book I made up as I went along, and that story truly was me throwing in everything I thought was cool.  I ended up with a story that not only had a secret society hiding magic from the rest of the world, I had Earth under attack by Lovecraftian entities, a main character who did a kind of alchemy by summoning demons into things to power them, a massive insectoid creature ripping itself free from under Las Vegas, and a girl who took out the bad guy in the final battle with the Power of Rock.

Yes, I just linked TV Tropes twice in one post.  I apologize for any free time you may lose.

The problem was, among all that cool stuff, there wasn't enough of a coherent plot.  There wasn't enough about the characters to really make them compelling.  And when I tried to redo the whole thing and make it work, I couldn't.  While I'd like to think that it was just all too cool to be forced into a story that made perfect sense, I know it really meant I'd gone too far.

It's something I had to learn as a writer.  Start with something you think is cool, and build from there, either forwards from an awesome concept or backwards from an awesome final battle.  A story cannot live on coolness alone.

Now, if you'll excuse me, I have to go snowboard down an active volcano while fighting off an entire clan of ninjas with chainsaws.