Just wanted to share a strange problem and our fix.
I installed Campy Super Record 11 on my S-Works Roubaix and no matter what I did I could never get the rear deraileur to run cleanly on the biggest cog of the rear cassette. Even when I manually pushed the deraleur in by hand it would not go far enough in towards the wheel and that was with the stop screw completely removed. After much measuring I discovered that the rear hanger was within the width spec as noted by Campy. They spec 7mm to 9mm as acceptable. The Specialized hanger was 8mm but there is some frame area that adds to the width as seen in the picture below. Our fix was to mill 2mm off of the mounting area on the hanger. After the milling everything lined up as it is supposed to. I did not notice any real loss of hanger stiffness either while I was adjusting it.
Hopefully this thread may help someone else who comes up against this issue.