In the New York Times this morning, an explanation of the strange, backhanded grip used by the blind Zatoichi in a series of samurai movies:
"When you grip a sword like that, it dramatically reduces your distance, so you have to engage your opponent very closely," he said. "If you notice in the fight scenes, he is basically right up against them. It's a style that actually works out pretty well in close, cramped quarters."
(Where, it is added, samurai employing traditional wide swings are at a disadvantage.)
Somebody went to a lot of trouble to work all that out . . . And then didn't say a word about it in any of the 25 movies.
Are you paying attention, young writers? Expend the effort to get everything in your stories absolutely right. But mention only as much as the reader absolutely needs to know.