I am going to have to disagree with this entire paragraph. The building of momentum thing is erroneous. You'll see running backs that are patient are not even close to full speed when they are near the line, reading blocks, and THEN they explode through once a hole opens.
As far as the empty backfield goes, it works. Simple as that. If you can get away with it, why stop? I agree we could use a little more play action out of our base formations but I see nothing wrong going with an empty backfield.