This website has top quality first class programs which I wouldn’t second guess. Explosive rotational work is also a vital part of any rugby players training program as rugby is not just a linear sport, it is a multidirectional game for strength and power athletes and the players need to be able to use there strength and power in all match situations, ie. twisting to steal the ball from your opponent.
All the rotational core work is greatly benefical to players because as well as improving rugby specific conditioning it also can prevent injury and imbalances.
Next time don’t make such an uninformed comment!!!