This can be done in pairs for support. Try to keep hips square and swing legs forward and back. Bend knee when the leg is at the back, like preparing to kick a ball. Feel in hamstrings when the leg is at the front and quads and hip when the leg is at the back.
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.