That's an "old mechanic's tale", sort of like an "old wives' tale". Anytime you can make a starter with field coils, (not permanent magnets like the modern ones) run backwards by simply reversing the polarity, I'll kiss your butt at high noon on any town square you name, and give you an hour to draw a crowd. The field windings prevent that from happening. A power window motor runs both ways by simply swapping positive and negative, but the field magnetism is provided by permanent magnets that can't reverse their poles. Not so with wire-wound field coils! The starter will run the same direction regardless of which battery post is connected to ground. Generators are ground-sensitive, not starters, but simply re-polarizing a generator makes it compatible with either ground polarity.
Jerry
