8x Antialiasing Turns Off Multi-GPU Mode on nVidia GEForce 7950

Starting about a year ago, nVidia modified its GEForce 7 drivers to remove
the 8xS antaliasing mode, which was compatible with multi-GPU performance.
Now you are forced to choose in the nVidia control panel between 4x and 8x.
4x gives mediocre antialiasing. 8x gives a good visual result, but if you
select 8x antialiasing you get a modal dialog warning you that this mode is
incompatible with multi-GPU support. Why would nVidia put such an awful
restriction into the drivers for this card? In effect, to get good visual
qualities you have to cripple the card's potential performance? To make a
confusing issue utterly unintelligible, if you then switch from 8x to 4x
antialiasing, you get a different modal dialog that warns you that going
from 8x to 4x will compromise the best "multi-GPU performance". This
directly contradicts the earlier dialog when going from 4x to 8x, by
implying that at 8x you can get a multi-GPU mode working.

At minimum, nVidia needs to clean up the text and explanations in these
dialogs. It's a mess. Can someone explain what these warnings actually
mean?

Can someone explain what are the implications of turning off multi-GPU
performance modes? If I want 8x antialiasing for visual quality, is there
any way to get both GPUs on the 7950 working towards rendering a scene?
Maybe in this case I would be forced to select one of the alternate frame
rendering modes 1 or 2?

--
Will