On a traditional ballast system, there is a piggy back wire to the starter solenoid so that for normal running, there is a reduced 6-9v supply to the coil, but when starting, that jumps to 12V to give it a boost. As soon as the starter is disengaged, the voltage drops.
I've been reading about the Mallory and as you mention, it does say you should have a ballast resistor in place.
