What is there to get wrong in your flattening dir example? I'd mv the internal dir as some other name to outside say dir2, them rm rf outer and mv the dir2. Unless there is something wrong in this approach.
I would agree with the rest, I always have to look up find and xargs syntax.
You've never mis-dragged something in the GUI or had a flaky mouse button which lets up randomly while you're dragging which left your folder "somewhere" that you now have to find?
I would agree with the rest, I always have to look up find and xargs syntax.