I have been told by an argentine colonel who fought in that war, that the Geneva convention was fully respected by both sides. Perhaps the book you refer tells other things.
This colonel was in the Gran Malvina island (that who is looking the continent) and he only received cannon hits by the Royal Navy. No man to man contact.
He received a British officer who told him that the Argentine forces surrendered. The colonel accepted it (he also was prepared to this event) and gave his gun to him. The British office did not accepted it, and invited the Colonel to dinner. Finally, the conversation was plenty of gentleness, no hard feelings. Both were professional colleagues and knew the war etiquette.
A good example that barbarian customs were not used.
I always thought that the military are "administrators of violence", as Liddel Hart says in his book.
