As we seen in the latest chapter, Luffy is carrying the cursed sword around and is preparing to take it out to fight. I believe during his 2 year training with Rayleigh, he would have been trained to an extent in using a sword. He may not be as good as others but i believe that Rayleigh knowing that they may enter Wano and also being a swordsman himself, would have trained Luffy in using a sword somewhat. We may see Luffy show these skills in this arc which will also add to his arsenal of powers. I believe we will see Luffy use a sword and show some hidden abilities we never would have thought he had. Thoughts?