It is an idea that emotions can be trapped in the body. The code
is just a way to locate what emotion it is. There is no need to do that in order to release an emotion though
But let's say you have anger trapped in your body, or for that sakes sorrow, it will emit a signal that you might pick up on on some level. It might disturb your ability to think clear, cause sickness or injury in your body; might even cause one to be suicidal? Yet when you release that emotion from your body it no longer has any effect on you, since it no longer is part of you.
Shamans talk about how traumas can be imprinted in your auric field, and when triggered you kinda loose control to your emotional response. It is basically the same thing. I suspect that the traumas in the auric field respond to trapped emotions in the body. So if you release an emotion you clear up a trauma in your auric field; or the other way around