The trigger is the same as other items that appear on agendas (eg the scrum, line out, ruck, maul etc) is the need to revisit points of law interpretation etc from time to time to remind and or update knowledge as laws etc are amended.
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......am appreciating that the majority will have arisen from topical incidents or communications from above.
I am trying to get an idea whether there is a chance that other issues get raised at the local society level, issues that may not be on the mainstream agenda (perhaps they might)?
This issue of lineout materiality being one perhaps?
You get a few people are gathered in a room, issues get discussed, you go off at a slight tangent and a conclusion is drawn on something unrelated resulting in treatment of an unrelated issue in a certain way. The outcome then gets shared amongst others in an informal way, e.g. around players, coaches or a forum such as this. Before you know it you have a wider audience perhaps informally adopting something as convention and we ultimately lose sight of where it originated without it necessarily have been sense checked or endorsed?
Does the society structure make sure everybody stays "on message" so we avoid situations such as this, i.e. as OB points out, suggested use at the lineout is not universal.
Materiality seems, to a degree at least, to have been left open to, "You buy into the ethos or you don't. We'll leave it up to you?". However the boundaries as to what it actually applies to are then left quite blurred?
Such things hardly serve to help the new referee along the learning curve.