Complex sentence: Patton's aide, Captain Jenson, is killed in the battle and replaced by Lieutenant Colonel Codman who assures Patton that, though Rommel was absent, that if Patton defeated Rommel's plan, then he defeated Rommel.
Split into simpler sentences: Patton's aide, Captain Jenson, is killed in the battle. Shortly after the battle, a new member of his staff, Lieutenant Colonel Codman assures Patton that, though Rommel was absent, that if Patton defeated Rommel's plan, then he defeated Rommel.