The reason I would like double buffering to be disabled is because of the mouse lag that it creates, and I am absolutely certain that double buffering is the root cause of all mouse lag in OS X (other than mouse acceleration, which I have disabled by using Razer's proprietary mouse drivers with my Razer DeathAdder).
If I boot OS X with an unsupported video card, the entire OS becomes very laggy, because QE/CI is not supported on the video card and is therefore disabled. However, double buffering is also disabled when I do this, as I can see screen tearing when I shake windows or move the mouse quickly. When boot this way, and double buffering is disabled, the mouse is perfect, just like it is on Windows. No input delay, no acceleration, just raw mouse movement.
I want to know how either double-buffering can be disabled across the entire system, or maybe even if there is a way to draw the mouse outside of Quartz, so that it is not double buffered.