I always contend that a good 10/15 can interchange seemlessly.
When I coached some juniors back in the day - way back - I had two good backs in the team and they were used to playing no.10 (as we call it now). They both wanted to play there and their dads wanted them to also; so I had them take turns at playing 10 and 15.
What I found out was that their play at fullback improved their play at flyhalf.
This makes sense because they are natural protagonists and one must always watch the position and movements of the other, and look for their strengths and weaknesses also.
It turned out that the faster lad started to enjoy playing fullback more, so he asked if he could stay there. It appeared to the dads that the outcome was caused by the great wisdom of the coach but though I basked in the credit for it, it was just serendipity.
We still nudged the wooden spooners for their title that season though, as I remember. They did better the following year when I wasn't coach. What does that mean?
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