Writing your Mind

How difficult is it to jot something down, when there is so much going on in your mind. They say, writing empties your mind, frees it from worry, pain and suffering. 

But what should one write? Isn't it difficult to write everything that is going on in your mind. You would say rather write a summary, a brief sketch, but wouldn't that filter your thoughts. So what's the purpose?

Shouldn't it be more like sailing a ship with your eyes closed and let the ship go, in the direction of the wind, wherever it takes.

But maybe the point is writing gives you a direction. When your thoughts are coming from all directions in your mind, now they have a single door to get out, the tip of your pen. So, knowingly or unknowingly you need to shape your thoughts, order them, restrain them, so that you can write yur mind.