(Not sure if this is your job any more?)
There is a lot of argument on the referees website about knock-ons into or inside the in-goal. Up to the 1970s, the laws said a defender could ground the ball and get a drop-out. Then they (gradually) changed the laws to say it was a scrum, just like any other knock-on.
Some referees argue that you can "play advantage" and give the drop out. The standard reply is that the defenders can only play advantage before the ball is made dead. Thereafter the advantage law does not apply.
Now there is the ingenious idea that if a defender picks up the ball and runs around the in-goal before making it dead, he has gained a tactical advantage by using up time and making the opponents use energy chasing him. When advantage is over, he can then make the ball dead for a drop out. I think that is an unreal view of tactical advantage, which should ultimately mean putting the team in a better position to score.
However there is one twist: if he runs around long enough for time to expire, no scrum has yet been awarded, so he avoids having one.
I forwarded my original to Dave Broadwell
Steve always favoured the hospital pass. Ha Ha things must be pretty desperate in good old Glos if this is a debate. It can only ever be a scrum one way or another. The referee cannot blow time until the ball is dead so someone will force the issue by grounding the ball or kicking it out of play.