Reality is grim teacher.
A "shoot house" is a roofless structure, laid out as a very complex house with lots of hallways, cubby-holes, and blind corners for fire teams to practice clearing. There are catwalks running above the house for the NCOs to watch the exercise.
Clearing - you've seen it on TV; the line of policemen or soldiers all piled up at the door of a house, and when they bust in they move rapidly from room to room in a specific pattern making sure each room, and ultimately the house, is clear of bad guys, and any good guys are secured and safe. For a team to do this effectively and not get shot, they have to practice intensively.
Myself and four others from our OPFOR group spent 15 hours standing in a shoot house acting as bad guys while team after team of Guardsmen swept through the house. We were asked by the NCOs to keep the scenarios complex, which meant a mix of friendlies and hostiles in the same house, and some social problem that needed addressing.
One scenario we ran many times had a father and three sons in the house. The father had lost his wife in an American- Insurgent crossfire. He was grieving and enraged to have his house violated by those he blamed for his wife's death. His oldest son would plead and attempt to calm the father and keep the Americans from hurting him. The two youngest sons were angry and armed and were militia sympathizers, who intended to kill the American invaders.

There were three possible doors to the house for the platoons to breach. We would wait in the halls straining to hear which one they would pick. Everyone of us knew that each scenario was one more chance for the soldiers to get better at their jobs, so the stakes for a good performance were high. As they breached, we moved into the proper rooms. The father and the older son would run to the entrance to confront the home invaders. Once the father saw they were Americans he'd go nuts. Screaming and pushing and storming up and down the halls yelling "get out of my house you murdering scum". He wouldn't comply to any of the verbal orders to get down, and stay contained. The older son, which I often played, would chase the soldiers up and down the halls trying to grab the guns away from shooting the father, pleading and yelling "don't hurt my father". For the less experienced platoons this domestic chaos was a real pause in momentum as they tried to asses the situation, and take control. A situation like that requires swift and aggressive control. They needed to detain and secure the Father and older son quickly, by subduing them, zip tying them and placing them at gun point, face down on the floor. The risk of the unexplored and uncleared rooms beyond was potentially deadly. With this exact risk in mind, the person playing the raging father would move swiftly up and down the hall in front of uncleared doorways in an attempt to lure the soldiers into splitting up and exposing themselves. The farther the raging father and older son were allowed to travel through the house, the greater the risk became. Eventually the soldiers entered the rooms where the armed younger sons were waiting. Sometimes the sons were killed immediately, sometimes they lived long enough to shoot a number of soldiers. Once the gun fire commenced from the back rooms the father and older son would go crazy. If they weren't tied, they would lash out at the guards, and try to get to the back rooms. If they were tied, they would kick and thrash and roll trying to inflict whatever harm possible on the Americans guarding them.
Once the house was cleared and safe, the soldiers would treat and evacuate their wounded or dead, then bring out the father and son. As they put us on our knees to do a more thorough personal search, we would scream and wail for our dead family. We pressed every human button we could think of to bring realism to the situation and make the soldiers tasks as difficult as possible.
One of the training goals we were asked to fulfill in this scenario mix was to attempt to press the soldiers into a 'bad kill'. A bad kill would be to shoot an unarmed and secured detainee somewhere in the process of securing the house. Even with the father character physically slamming the soldiers up against the walls and dragging them off their feet, and trying repeatedly to get off his knees, and the older son grabbing at weapons, we were never shot out of fear or frustration. I was proud of them. Each team was able to subdue father and son in different ways, all abrupt, and aggressive, but non-lethal.
After several hours we had some down time, and I could get my thoughts in order. Joey and I were talking about the platoons breaking into the house, and our reactions to it. He commented, "...I was hiding near the front door and I heard 20 M4 bolts being drawn back...that is a scary sound...". The violence of action really struck me. Within seconds of coming through the door there were soldiers in the room with you and you were dead. It was shocking how quickly they were able to react as a team. Often I was waiting for them, with my gun trained on a spot in the hall, and I would be able to get off a wild shot or two, and they would be on me - and had killed me before I could withdraw or really react at all. It was impressive.
As the day wore on we ran every conceivable form of human behavior both friendly and hostile; Hiding and jumping out, running to evade, running towards, trying to escape the house, placing gunmen outside to press the outer parameter guards, shooting from open windows, barricading ourselves, throwing things, blocking the hallways with obstacles. If we were bad guys, we died within minutes. If we were good guys we were face down and zip tied within minutes. We killed or wounded a number of American soldiers, and in a tight home environment I saw exactly how terrible and complex this can be.

One scenario stands out as a terrible lesson for everyone present. It got dark and we were running the last few iterations of the day. A dark house is a bad place for a team to be entering and can be extremely challenging and dangerous. The newest platoon working that day hadn't brought enough flashlights - they hadn't expected to be working in the dark. There was no night vision equipment available. Sgt. Ezelle was angry and made some opening comments about being prepared for anything at any time. The platoon had two flashlight amongst them. Sgt. Ezelle came over and gave me the word to go hard on them. The look on his face read, 'lessons are going to be learned'. I placed one of our guys hidden outside of the house in hopes of entering in behind the platoon and inflicting casualties from an unguarded (and un-illuminated) rear. The rest of us were in the house, hidden well in the dark. As the team breached the door, and started moving around, one soldier shot another one while coming around a corner in the dark. From the closet where I was waiting I heard one of the observers from the catwalk yell out, "fratricide! - you are dead." I heard fire coming from outside the building. The guy we had outside (Joey) was starting to move. I kept hearing his gun firing but no return fire from the soldiers. Inside, the soldiers were yelling and calling out to each other, frustrated and frantic in the dark house. Tempers were quickly rising. The observers were calling out hits - "you are dead, you are wounded, you are dead". The team had only cleared half the building and were stalled with not enough men to move forward, attend the wounded, and still keep a rear guard. They also couldn't see anything. Our guys were popping up and shooting them at every turn. I came out of the closet and shot two coming around the corner. I died. I laid on the ground dead and listened to the aftermath unfold. It was awful. The platoon leader was radioing for emergency extraction. Sgt. Ezelle, on the other end of the radio was telling them they had to secure the building and that help was 20 min. out. The guys started to get frantic, bouncing from one impossible task to the other, not sure where to sink in their teeth. Sgt. Ezelle ordered them to bring in the dead from outside before the bodies were defiled and equipment was stolen. He instructed them to place all their dead and wounded in one room near the door so the extraction team could load them up quickly. The three guys left dragged in all their dead into the main room. 16 total. The scene played itself out, the three remaining soldiers were able to get the necessary tasks completed, and the help finally came. Sgt. Ezelle called the scenario over, and instructed all the OPFOR to get up and reset the scenario for the next group. He had everyone come into the main room, where the dead were. He shined his light over the packed room. I noticed he didn't say much, just, "take a good look guys, this is what unprepared yields....now lets talk about what you did right."
Reality is a grim teacher. The platoon left the site somber and a bit pissed. I was glad. Better here than there. It was a lesson I hoped they wouldn't forget - ever. I called up to Sgt. Ezelle still standing quietly on the catwalk in the dark. I was worried that we had overdone it, "Sgt. Ezelle, it that what you wanted?". He replied, "That is exactly what I wanted."
If you want to read more about the Oregon Nat Guard and specifically the 2-162, pick up John Bruning’s book, The Devils Sandbox. He tells the story of the 2-162’s deployment to Iraq.