Players start on their knees and roll down to their left or right depending on the feed to catch the ball.
The feed can be made to either side and the keeper should be ready to react - extending their body to catch the ball.
World Rugby has reportedly conceded Aaron Smith's disallowed try in the World Cup final should have stood.
"It is not only useful for staff who are experienced but a valuable tool for those subject staff who have to take teams."
The variety of sessions across sports - sometimes we steal session ideas from one sport and use them with another.