Thrand and Eldgrim demonstrate and Method of manipulating the opponents Shield by using the large round shield center boss with Nial or indentation. This technique of pushing down on top of shield I first saw John Clements demonstrate on the Ulfburt documentary " Secrets of the Viking Sword " and would like to give credit to him for us experimenting with this idea and finding more uses for it. So set back grab so mead or ale and enjoy the combat.
Secrets of the Viking Sword (2012) full
http://youtu.be/nXbLyVpWsVM