It would not be giving him a second rune. Rather it would be uniting True Wind as one again.

There can only be Twenty-Seven True Runes, having more is a paradox and nature abhors paradoxes. Uniting the two True Wind Runes should fix the paradox and should have little affect on him.

[pause] I knew Luc when he was a child. I would very much like to see a future where he is not burdened so.