Comment 19 for bug 136336

I wanted to do something similar, so I found another way to get similar effects. I do two things:

1) Instead of minimizing the windows, just move them over to another workspace. I use the Emerld Theme Manager with a theme that gives me an available drop box on the top left corner of the window to move it to another workspace.

2) When you select your plugin in Compiz (in your case the 'Shift Switcher', use the option "Initiate Windows Picker for All Windows". Enabling the All Windows will display all windows in all workspaces.

That should give you very similar effects. Finding the easiest way to move a window to another workspace would be your best way to "minimize" your desktop clutter.