According to a Dianne Rehm interview with a noted Ben Franklin biographer; many Franklinisms have been invented left and right by American book publishers searching for "American" role models for kids in the newly born nation. They couldn't reach back to the continent which they have just severed ties with for cultural lore, so they had to invent it as they went, at least for the first two or so generations.

Franklin himself made no attempt to refute the grand achievements attributed to him in his day (e.g. "I will neither confirm nor deny that I have superhuman powers and can kick ass in major ways".)