Help needed getting Full-Screen Video working right

I was playing with the new 52.16 NVIDIA drivers for my GeForce FX 5600, and
I had Windows XP Media Center Edition ("MCE") running in a window. Suddenly
my TV was showing *full-screen* Live TV, whilst my monitor remained
windowed. I was able to open Word etc. and still watch Live TV on the
telly, full-screen.

This isn't supposed to be possible with MCE.

Here's how to recreate it:
Open MCE Live TV, windowed
Open NVIDIA Display Properties
Make sure you're in Clone mode (PC monitor primary, TV secondary)
Click 'Full Screen Video' in the GeForce sidebar
Enable for Secondary Device
[at this point your TV may flick to full-screen, if not...]
Click 'Change Resolutions' in the sidebar
Switch the refresh rate to something else and Apply
Then switch to 60Hz (for the best display) and Apply

You should now have full-screen video on your TV.

If you can't see the shuttle controls in full-screen mode, resize the window
on your PC monitor until you can. You should see all the MCE graphics such
as More Info, RW, FF, etc.

That was the good news, now the bad news:
When you click the green button, maximize/restore or close/open MCE, it
stops and you have to go back to Display Properties to fiddle again before
it comes back.
It doesn't support widescreen so you'll get a 4:3 image and no MCE Zoom
option

Can someone tell me what's going on with this?! We know MCE doesn't support
Overlay, but have NVIDIA invented a new way of showing full-screen video?
If so, it works quite well when it works, but not perfectly sadly. Anyone
know how to fix the bad news above? I've provided the first step
--
CJSnet

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