Refresh preview thumbnails

I love the Aero peek preview thumbnails, but after having many windows minimized for awhile the thumbnails will go blank. I have to maximize each window to get the thumbnail to refresh. Is there some way to fix this?

I have already set "Save taskbar thumbnail previews" aka HKCU\Software\Microsoft\Windows\DWM\AlwaysHibernateThumbnails[1]. I came across two similar descriptions of the problem[2][3] that seem to indicate maximizing is the only way to tell the application to redraw. I looked around for a way to increase the DWM buffer size but could not find anything on that front.

Is there some dark magic 7+TT can do to keep me from having to click through all my windows to refresh their thumbnails?

[1] http://www.sevenforums.com/tutorials/127881-taskb...
[2] http://superuser.com/a/119590
[3] http://www.neowin.net/forum/topic/867016-taskbar-p...