Just spotted this picture in the lawbook
https://laws.worldrugby.org/?law=19, which does seem to suggest the SH of the team in possession must be behind the back foot 'when not playing the ball'.
Exactly. I think we are over-complicating this gents, but for what it's worth this is what I think.
Perhaps "playing the ball" wasn't the best phrase they could have used because to me that implies that the SH is actually holding the ball. I reckon "
Following the ball" would have been better wording.
If the SH is
following the ball through the scrum, then the ball is his offside line. Both SHs have to stay close to the scrum, the SH for the team not in possession has to keep
both feet behind the ball and the SH of the team in possession can straddle the offside line but can't have both feet in front of the ball.
If neither SH wants to follow the ball through the scrum, he can retire to the HMF and that offside line runs the width of the pitch. I don't think it's particularly complicated. :chin: