Yes, the 12v coil will burn your point up prematurely IF, the coil is one without an internal resister, and no external ballast resistor is used. If you use a 12v coil with an internal resistor, you don't need the external ballast resistor.
The old 6 volt systems didn't use ballast resistors because the 6 volt system didn't push enough current through the primary circuit to burn the points. When they went to 12v they started using the ballast resistors to knock the voltage to the coil down to somewhere in the neighborhood of 7-9 volts. This lessens arcing at the points and extends the life of the points dramatically. When measuring voltage at the coil you have to make sure the points are closed and current is flowing through the circuit. If no current is flowing, the meter will read full battery voltage. You can also check the voltage with the engine running.
