I am running a game (finally) of Conan but it is basically D20 with minor modifications. I have 4 players. All are new to D20 and only 1 has a lot of role playing experience. I am trying to introduce combat. A player asked about the HP mechanic and asked why it was that I person who is very wounded can hit as well as he could at full heath. I told him HP were an abstract system representing wounds and fatigue together. And I pointed out that any game plays a balancing act between fun and playability vs realism. Does any one know a better answer?