Moderation is best when it is impartial. It's hard to be impartial with your own thread. And if you want that much control, why not just hold discussions with yourself?
It would be very uninteresting. It would be like, say, Tim posts a thread and Tim's friend Bob then posts, giving Tim exactly what he wants to hear, but then Ted, Tim's critic, comes along and posts something Tim doesn't care for, so Tim bans Ted from the thread. Tim's friend Sally posts - nothing contrary, just more "You are so right, Tim." Everyone who holds a contrary opinion will decide not to post in the thread and then there would be no more debating in the Debate Forum.
"True Love is the only heart disease that is best left to 'run on' - the only affection of the heart for which there is no help, and none desired." -Mark Twain
"The mind is its own place, and in itself can make a heaven of Hell, a hell of Heaven." -John Milton
"...whoever you hate will end up in your family!" -Chris Rock