1) Federer won his 5 consecutive Wimbledons well after the grass courts of Wimbledon had been slowed down (even though apparently they have been slowed down a bit further recently). This is not to say that he is not a very rounded player: he absolutely is and has an incredible ability to pass from defense to offence, but he has not been playing the type of attacking game on grass that used to be common in the days of wooden rackets and a very fast grass – faster at least earlier in the two weeks of play. Borg won his 5 consecutive before in those old times of fast courts and wooden rackets.

2) The slowing down was in good part related to the deep changes in the game due to the change in racket materials and sizes (frame and strings), and, separately, the evolution of player training and conditioning. It’s impossible to understand the current change of play on grass by considering only the changes to the surface and balls.