The deadline assistance makes logical sense. As a theatre person, everything's a deadline. The show will go on, whether you're ready for it or not! Similarly if you're writing a play, there's a certain date where you simply must have sides for auditions, and a mere 72-hours after that you'd better have a script to give to the actors!
Novels are harder, though, simply because they're enormous in scope and have a tendency to get richer as you write them (at least for me), and so I fully understand why Douglas Adams famously said: "I love deadlines. I love to wave at them as they pass me by." (A nice nod to which was in Pirates of the Caribbean 2.)
But my justifications for why insomnia is a blessing are as follows:
Or on a slightly more silly note:
So I wonder...when do other people find their genius flowing?