Good article. I'm a strong believer in the three-act plot as the best/main way to tell a story. Even when I deviate from this, I don't really deviate from it.

For example: My most recent novel, dystopian romantic satire Peaceful Quiet Lives, has two distinct halves (each half set in one of the two nations formed following the second US Civil War), but each half has a three act structure (for reasons I won't get into here, the novel is incomplete if you seperate them).

On the other hand, some novels and films benefit from having more than three acts. Raiders of the Lost Ark is a good example.

I'd also recommend Robert McKee's excellent screenwriting book Story. He is a great defender of the three-act structure.

Thanks again for your article.