How do I get rid of my doppelgangers?

I'm building a multiplayer 3d fighter, and I instituted networking through http://www.paladinstudios.com/2013/07/10/how-to-create-an-online-multiplayer-game-with-unity/ . I have the controllers instantiating, and the cameras separately tracking both characters (just testing with two for now). Thing is, when there's no input from one, person, the other can move BOTH characters... kind of. Because the other player only moves on one screen, and pops back to his "real" position as soon as the owner moves. So if your opponent stops moving, his character just runs around seemingly under your control till he moves again. It's really kind of gamebreaking.

I've been looking into solutions like changing network synchronization to unreliable so that it just constantly updates, or using the ismine or isserver/isclient methods, but none of those seem to exist in the current version of unity, at least not the methods of using them which I've come across. How do I get rid of my doppelgangers? Is there an in-code method in current unity to change to unreliable? Is there anything like ismine or isserver/client that I still have access to?