When I say "walk the dog" I am saying you have to make it crystal clear. It is like the difference between a criminal case and civil case in the courts. The CRSC board makes you prove everything. Also one of the common mistakes SMs make is sending too much. If you send your whole medical record, it will hurt you, not help you.
They want to see the notes that clearly state the orgin of injury. MEDEVAC orders for your injury will be good and then the follow on care. Did you have surgery right away, or did you do physical therapy? Also being over in Iraq and wearing all your combat gear will not be enough. You have to show the gear was the cause of your injury during combat operations against the enemy.
Let's say soldier A is a supply sergeant and never leaves the FOB. He has to wear his gear from his room to work, and then again going home. He also has to where it when he goes to the shopette, or anywhere else he is outside on the FOB. About halfway through the year his back starts bothering him and he starts going to the TMC. He gets a profile, but his back injury never gets better. He gets boarded and goes out for the back injury. He trys to file CRSC on the above scenario. He will have a hard time getting it approved by the way the criteria is written. His primary claim would be based "armed conflict" and they will deny it based on the fact he never engaged with the enemy.
Soldier B is also a supply sergeant, never leaves the FOB and has all the same requirements. While he is walking to the chow hall the incoming alarm sounds, and he runs for the nearest bunker. The mortor impacts on the FOB, but not close to him. While he is waiting for the all clear, he notices his back hurts and goes to the TMC. He gets treated and goes back to work. For the rest of the deployment his back bothers him and upon returning home, gets med boarded. He will have a much better chance of getting CRSC based on Armed conflict. He would submit the sitrep report, or a witness statement that there was a mortor attack on "x" day. Then he gets the notes from the TMC that shows his injury. Those notes will say how he hurt his back. Lastly, writing a clear and concise narrative on the DD 2860 wrapping it all together. This SM will have a very good chance based on that evidence.
Walking the dog is the most important part. You want to make it as clear as possible and in a format that makes it easy and logical to adjudicate it as a yes.