Armchair viewers get a glimpse of the future and it looks to be laser-guided | Richard Williams

For all its help in straightening out rugby union and its recent assistance to Eliud Kipchoge, what effect will green-line technology have on the off-the-cuff spontaneity of live sport? While the glorious phenomenon that is Simone Biles was winning a fifth all'around world gymnastics title last week with routines that included a triple-twisting double backflip during the floor exercise and a two'flips'two-twists dismount from the beam, she was doing things that the human eye could barely take in...