"What is the 2D Cartesian Coordinate System, Lonewacko?"
The "Cartesian Coordinate System" is something almost everyone is familiar with. Don't worry, this isn't hard math! It's the xy-plane, where you have the x-axis extending left to right, and the y-axis extending top to bottom, and they meet at point (0,0). Something you all remember from your early education.
Now, why is this in the Politics category?
Because, you can agree to offset something placed in this coordinate system. That is, you can agree to place something a little to the left. As long as you place everything else a little to the left, everything lines up. You can agree that the point on the x-axis is 3 units to the left and at point 0 on they y-axis is your new origin, and as long as everything else is moved 3 units to the left, everything's OK.
That is the mathematical explanation of John Carroll, editor for the L.A. Times (laobserved . com/archive/001834.html).
You see, in Carroll's world - as in the world (tommangan . net/printsthechaff/archives/001402.html) of many other newspaper editors (tommangan . net/printsthechaff/archives/000784.html) - their origin is a few ticks to the left. They think they're at the center, but they're actually to the left.
Xrlq has more here.