According to the SCTA2010 rule book (3.I.1 pg31), "All cars with other than stock fuel system shall have a fuel shut-off within the drivers reach". I suppose this could be the ignition switch, or other toggle switch on the dash. The third sentence in that section says "All electric fuel pumps shall have an inertial or other positive "shut off switch" e.g. microprocessor controlled , or oil pressure switch".
So, I think your assumption of two method is correct, at least that's how I interpret it as well.