That doesn't work because they are considered "out of play" and as such cannot be involved in the play at all and cannot be put on side.Your props would need to be 54kg at that rate. Still it's an interesting idea. Would that mean we send a few forwards up a tackle early so they can wait with the opposing fullback but be still until said kicker arrives or could an on side legally chaser activate the on side thing for early arrivals?
You are not supposed to pass the point of the play the ball until the ball is played.