In fact the whole team wore skin suits. For a team to wear skin suits for a road race is very rare. David Millar's Garmin team did it one year for the Champs Elysee stage of the Tour de France. That stage was ironically won by Cavendish and Millar was the GB captain for the Worlds. Out of picture the management team also had set up around the course communicate information to the team. Race radios which are common for races like the Tour de France are banned at the Worlds and Olympics.
These are 3 little changes which individually would probably not make a difference. However add them together along with all the other aggregated marginal gains that GB cycling chases and you start to make significant gains. For GB cycling significant gains were 6 amazing medals. And for Cavendish something else too: