You may now find it is sometimes possible to go back and edit your last move. Any oddities, let me know. I think I've closed the loophole which would have allowed an infinite number of new games to have been started.
[Rab] That 'whoops' thingy made me jump when I posted earlier. It reminded me of that vaguely guilty feeling when one sees a policeman. It compelled me to re-read my post just in case I'd said something a bit wrong.