Thanks Ulodesk.
That does help but essentially the document pane does not move at all. The blue gap at the left is still there. I guess this is the problem with 16:9 widescreens. Great for movies, but too wide for working with a document (I find it irritating to read text extending from the left all the way to the right), yet too narrow for working with 2 snapped side by side.
A workaround I found was to use Winsplit -
http://winsplit-revolution.com/ - to snap the window to 75% of the horizontal screen estate. So it looks like this:
Cheers,
Jay