How does it redefines speed and acceleration?? "While the P100D Tesla versions are even quicker off the mark than the hottest landshark from Stuttgart, the rep

How does it redefines speed and acceleration?? "While the P100D Tesla versions are even quicker off the mark than the hottest landshark from Stuttgart, the repeatability of such a task is what allegedly separates the wheat from the chaff." Not sure what is wheat and what is chaff in this context.