Yep, Ive tested it myself.
All the code was already in the 4.8 plugin to enable it.
with QAhead off,
Increase screen percentage of a basic scene in small steps until frame rate halfs to 37.5fps.
Turn on Qahead.
Watch framerate return to 75fps.
Unfortunatly as we currently cant disable vsync that is the only way I could think of testing it.