Ray can get away with a lot of nonsense in his foreword, assuming it's only read by people who support his position. However, thanks to the NCSE and other bloggers, hopefully the scientific and educational communities will sit up and take notice of the blatant distortions and misrepresentations going on.
But when he's in dialogue with a proper scientist, then there's much less room to maneuver. Especially in print, as Gish Gallops are much harder to do when there's a paper trail.