Seems like a fan 'solution' to a fan 'problem'. There isn't anything in the movies to suggest that Han using the lightsaber was problematic. There was nothing to explain until other fan theories were made despite being in conflict with that scene in the movie.

I was under the impression when I first saw that scene that lightsabers were just meant to be technology - the more "civilized" version of a blaster in the way swords were once seen as more civilized than guns, but still basically just a device. Han knew where the button was to turn it on, which was all he needed to know. In the same way you wouldn't have to be a samurai master to use a katana to cut a watermelon.

Which is why this universe is so damn awesome!