Oftentimes with creative endeavours a break must be taken so that the project can be approached with a fresh mind. When you get too close to a piece of work you begin to lose sight of the whole picture and often miss mistakes. This is true art, writing, music, and surely film, as well. If Nolan needs to take a break, I say let him. He's pretty much guaranteed to do a better job when he's content and doing things at his own pace.
Finally, thank God Nolan made The Prestige first, because I love that damn film with every fiber of my being.