I'm not sure any single clue can help. From just a quick read, I had a hunch, but had to use every clue to confirm it. I don't believe it is possible to solve without every clue with the possible exception of #5 and a strict or literal interpretation of the premise that they are not respective. I probably could have done it without paper, but it would have made my brain hurt.
A tic-tac-toe board, and a 3 point map is what I used.