Many times I struggle with the concept of moving meditation in Sanchin ... achieving the state of empty mind -- what that feels and looks like. I came across this quote from Takukan Soho, a 16th Century Abbott:
We have to trust in that perfect unadorned perception. The very mind that wants to control things is the mind that's caught up to begin with. When you're caught up, you have fewer possibilities. Your mind can manifest in more ways if you keep it from taking form. Technique is just a means for understanding that. Do you understand what it means to not let your mind take form? When you allow the mind to harden itself into a shape, a feeling, an intensity, technique, or strategies rather than allowing that clear, mirror like perception to arise, that is allowing the mind to take form.
The technique is something you do while you try not to let it interfere with the spaciousness of your mind. If you let your mind take form, it becomes localized. When you feel that happen, Return and come back to a formless state. The more that you can do that, the more you'll be your own person. The less you can do that, the more circumstances will dictate to you who you are at every moment.