Blender 3D: Show and Work simultaneously on two or more scenes, same file I use Blender 2.75 on Win 7.

I some times create one blend file and a first scene.

Than I duplicate the scene (once or more times as I need) and I make some variations to consider more possibilities for the situation I have to study.

I frequently have the need to visually compare in real time the two (or more) scenes for various reasons. For achieve this I need to have two (or more) scenes of the same file showed on the computer screen simultaneously.

The menu view > Duplicate area into new window, allows me to look the same scene from different perspectives and observe the same scene from as many points of view as I need. But I can't do the same with two or more different scenes of the same file.
The only thing I can do is to switch from one scene to another with the scene selector that switch the scene for all windows. This doesn't allow me to show two scenes simultaneously but just one at once from different points of view, in each window.

What I want, if it is possible, is to have two or more windows of the same file opened on different scenes. The problem is that acting on the scene drop down menu switches the scenes in ALL windows, even the separated ones.

I tried the solution proposed by iKlsR♦ in this page Is it possible to work on two or more files at the same time (or open multiple Blender instances?)
but it doesn't work: the scene is switched on both opened windows.

Is there any solution or any option to solve this situation and allow me to show on screen simultaneously two different scenes of the same file?

Thanks in advance.
Just for the sake of completeness here I'll leave a more proper answer.

Go to File > User Preferences > Interface > Display and uncheck the option Global Scene.



The "Global Scene" option enforces displayed data from all editors to belong to the same active scene. If you disable it you can show data from different scenes in different editors if they belong to different OS Window. You will need to create an Info editor for each separate window to control which scene is displayed there.