You can scrum down together time after time.....but not celebrate a try?
I'm not a doctor but I can see some logic here. In the scrum only the front row & maybe second row will actually be breathing on each other. In a try celebration the whole team come in and hug and dance around.
Also scrums are an integral part of the game so the risk is acceptable. Try celebrations are not necessary for the rest of the game to take place so trying to reduce un-necessary risk makes some sense when you think about it.
There's also a bit of me that wants to return to the good old days of a calm manly handshake when a try's scored (although that would now have to be an elbow touch!)
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