

The image above shows some basic anatomy. Let's take a cursory look at what's going on with kesagiri. Why is kesagiri so devastating? It might seem that it is passing many more bones than the kiriotoshi strike and cannot deal much damage. It is important to note that not only the body is affected by kesagiri but also the limbs. Some pass through the rib cage and some stop just below the xiphoid process. From here the attacks come down and have different intended stopping points. This sword strike comes from the upper positions often referred to as jodan. The illustration above shows various kesagiri angles that some iaido/iaijutsu schools use. Many schools use kesagiri in place of the shomen-giri. While still important, I find kesa-giri to be much more interesting and versatile.

My understanding is that this strike is an ideal cut. There also seems to be a few real-world injuries evidenced on skeletal remains in Japan. A glancing blow, while very painful indeed, is not going to do the trick. I would classify kiriotoshi and the median plane strike as practical but not always a guaranteed mortal wound due to the need for extreme precision of cut placement on the rounded surface of the human skull using a katana. Therefore other types of angles are also taught. During a sword fight, chances must be taken advantage of and a myriad of strikes and techniques are used. Even harder if the opponent has headgear. It certainly can be fatal, but again the rounded and curved surface of the skull does make it hard for the katana to always deal a deadly strike. This cut is usually reserved for the final blow or coup de gras. It is not always preferable to use this strike, and it seems that historically, many haven't in actual battles. To protect and house the eyes, and brain. That is, of course, one of the reasons for the design of the skull. There is a potential for such a cut to glance off the rounded structure of the skull. I use the word fail, and it sounds as if I am calling this cut non-effective. The one issue with this cut is that the skull is shaped in such a way that these types of cuts have a lot of variables that can cause them to fail. The first target that is being affected by such a cut is the skull.
