The only elucidation on the circumstances of OBL's death I've heard is that he was unarmed, did not use his wife as a human shield, but apparently still resisted capture. I don't want to speculate on details, but I can tell you this: every minute of that 40-minute mission was planned out and practiced endlessly before Seal Team 6 arrived. They would not have killed OBL if that was not their plan from the get-go.