wes,
I have been using 12v 235/261 Pertronix ignition and Flamethrower coil for over 10 years with no ballast resistor. I had called the Pertronix Technical Support about this and, after a long conversation with two people, they concluded that no ballast resistor would be necessary.
However, since that time, more than a few people have reported that Pertronix Technical Support has informed them that a ballast resistor was necessary in a 12v 216/235/261 application (with or without their Flamethrower coil).
Just to add to your (and our) confusion,
look at page two of these installation instructions. It seems to indicate that if you had a ballast resistor with your points, you would keep the ballast resistor when using the Ignitor.
