If you think, you are late. If you are late, you use strength. If you use strength you get tired. And if you get tired, you die!
Jiu Jitsu at the end of the day, is the art of expressing yourself honestly. Everytime you put on a Gi, you can't lie.
When you react, you don't give your mind the time to get filled with emotions. You are devoid of anger, fear, and frustration; you are simply moving.