The tradition came from the medieval times = battle times. Each of them had a sword and a shield. All the shields were made out of metal, shiny, sturdy and stunning. The whole group kept beating against the shield with a sword. Not only the sound was beautiful, but also they looked beautiful, when repeating the movement of the swords and the shields in a coordinated, organized environment. They practiced together. Right hand, left hand. Agility versus power. Since the war was won, they used it as a tune making devices. Together they practiced their music. The only problem was to find a big enough ground for all the players and the audience to admire them.