The hands are tools, nothing more.
The true power behind manipulating energy is your mind.
So let's not say "eyes", let's use "mind" instead. Your eyes are meant for sight not energy work. The eyes would not work without your mind. Your mind is what does all the work spiritually, regardless of whether or not you use tools. Tools are only used to help you to recognize that something is being done. In everyday life, we use a variety of tools--our hands, utensils, toothbrushes, combs, etc. We use our physical senses to gather information (again a form of tool). And it becomes difficult for some people to get out of that mindframe when stepping into magick.