I know I have discussed this topic before, but it seems like a subject that needs to be discussed over and over again as there are many people out there who think that they can end a fight like Joe Pomfret did at his recent fight.
First of all, let's be honest, Joe is an incredible talent (and fun to watch). What he does is an example of his many years of training various arts and martial ways (i.e. Uechi, BJJ, Marine Corp., etc.). But for the rest of us, the distraction (i.e. atemi) is an essential part of the fight. Let's face it, when you are rolling along the ground with someone who may seemingly get the advantage on you, are you going to start playing by the rules??? The answer is rightfully no. Do what you have to do to get the person off of you and then go to town.
But what do you do? What if the person is doing this or that? There is no correct answer to those questions. What you have to do is look at what is vunerable. And yes folks, I don't care who the person is, they always leave something open; you just have to find it. That doesn't mean that you have to wail on the person once you find the spot. If it is a reasonable area, you may not have to hit it that hard to move the person off of what they were doing.
The key though is to react once you do strike the area. Don't sit there like a deer in the headlights. Strike and move! Heard that before in you training??? I bet you have. Even in Uechi sparring, that premise is paramount. Hit and MOVE!!
The atemi in itself is a killing blow technically, but in a fight you don't have to use it as such. I teach it as a distraction in order to do what I really want. For example, a person is sitting on top of me while I am on the floor (let's assume I didn't get to the guard), a quick shoken to the ribs moves him enough enabling me to move either to the guard or out of the situation. I don't mean a punch to the ribs, but using constant pressure in between a rib or two. That is a simple example, but those of you who have worked with me, know how effective it can be.