Think about the type of game which was best suited for the faster courts....then seriously apply Roddick's game to said surface.
I cannot see him outplaying Kraijeck or Goran during that period. Then, add in Edberg, Becker and--of course--Sampras, and the chances of a Wimbledon victory appear slim to none. Regarding dominant forces at the other majors, in the 90's, take the USO; remember Sampras won 4 USO in that decade ('90, '93, '95 & '96), then, Edberg, Rafter and Agassi all won two each, so there were no fluke champions, with Sampras, Edberg and Rafter proving they were formidable enough to repeat. Roddick against any of the named players does not add up to a Roddick victory, considering how each played to win their respective USO titles.