... yeah, nothing is moving your windows, it's literally just a preview. This is like saying that the Windows menu bar preview is duplicating your windows.
The Windows menu bar doesn't move. The activities overview moves my screen. That's unnecessary and intolerable ;-) We all have our own quirks.
By the way, I added a Windows style task bar to the bottom of my desktop. It autohides and that's OK because it doesn't move my windows upward when it appears.
