Sorry, I missed your reply Marc.
You copy music from the two staves of the piano. Then you select one point in one piano staff. Both staves are being copied perfectly on both staves, not everything on the staff you selected. I personally find this very logical and convenient.
I don’t really follow your explanation I am afraid, would you care to elaborate?
However (@Derrek), I do understand the general advantages of the approach of instruments rather than staves. I just don’t see, as I said earlier in the thread, the use of the resulting behaviour in this particular case.
Anyway. Not a big deal.