I started writing a chapter and, frankly, it was spinning its wheels. I had no idea where it was going. I had some fun dialogue and a few laughs, but the plot wasn't being advanced. Why? Because I couldn't figure out where to take it. I was afraid to have my characters take any action until I knew where I wanted the plot to go. But I couldn't decide. Catch the bad guy? Almost catch the bad guy? Kill the bad guy? None of the above? If choice D, then where to now? I just couldn't make up my mind what I wanted to happen next.
So I decided to choose option E: surprise myself. I put the main character in an iffy situation and see what he would do. He did a cool thing, it turns out. And as a result of this cool thing, he made a startling discovery that will lead to some neat plot points down the road. And the exciting part was that, until about thirty seconds before they travelled out of my brain, down my arms, into my fingers, and onto the screen, I had no idea what the words and events were going to be.
I have to admit, while it was a fun way to write, it was also quite daunting and exhausting. On one hand, I was so thrilled by what happened that I had trouble getting to sleep. On the other hand, despite being restless, I was really wrung out. Actually physically spent. It's kind of like hacking through the jungle with a slightly dull machete (though the dull part is probably only because it was me). Once you get to a clearing, you really appreciate it, but you'll be sore when you arrive. I don't mind visiting from time to time, but I don't want to live in the jungle all the time.