Reading the OP, I see a distinct difference in the action. That's why I'm throwing the idea between the two out there and see what everyone has to say. There is no case play for what happened in the OP, and the case play that has been presented doesn't seem to fit the OP. I know Mark makes a good case for the warning because of the prevention of A's ability to make the throw-in, and I would almost go along with that thought process. The OP and the lack of case play basically brings into play some thought process on our part.