What locates the flywheel to the crank? The magnets have to pass the coil at exactly the correct point.With a module I think it should fire at any point whereas with the points, they need to open at the correct time the magnets pass the coil. Problem is with the modules some of these ignitions are pos earth and others are neg earth. I can't help on that point. Some points work as you describe open for most of the revolution, close briefly, then open again to create the spark
