Now suppose that I need to swap my active skills around so that Disintegrate is no longer an active skill. What happens to the rune when I put Disintegrate away? Does the rune get moved back to my inventory? Or does it remain attached to the disintegrate skill (even if it is not active) - effectively hidden from sight when the skill is not active, giving me a 'free' extra storage slot for it?
If it moves back to my inventory, what if my inventory is full? Does it drop on the ground? Or lock the skill so that I cannot change it until I have cleared some space in my inventory? If it drops on the ground - I can see potential for some high level rune theft.
I'm aware that the 'unattuned' business about runes is not currently set in stone, so even if there are no solid answers to these questions at the moment, what would you want the answers to these questions to be?