Dockable Windows and Double Clicking

I noticed the other day that when I double click on the tab of an active docked browser or palette that Revit will "pop" the window out of the docked position. It will land somewhere on screen, probably near the middle of the Revit window. If you move it somewhere else Revit will remember that the next time.

If you double click on the title bar of the "popped out" window it will dock again. Activate a tab, double click...pops out...double click on title bar pops in. Interesting... here's a video, no audio.