Both players side step along the tramlines throwing the ball (underarm)to each other until they reach the net and then return to the baseline doing the same thing. Catching the ball after one bounce is a good start.
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.