I completely agree with you that poetry is also a formal use of language. Indeed, only form allows us to hear the tone of the words, and it is precisely because verse is sonorous reality that words in it are no longer subject to the sole authority of conceptual thought. This enables us to perceive reality otherwise than through language. Form in poetry silences the conceptual meaning of words; it is therefore the condition of the direct gaze upon the world.
Here’s another gem:
For poetry can only be a partial approach, which substitutes for the object a simple image and for (our feelings) a verbal expression—thereby losing the intimate experience. On the other hand there is nothing before language, for there is no consciousness, and therefore no world, without a system of signs. In fact, it is the speaking-being that has created this universe, even if language excludes him from it. This means that we are deprived through words of an authentic intimacy with what we are, or with what the Other is. We need poetry, not to regain this intimacy, which is impossible, but to remember that we miss it and to prove to ourselves the value of those moments when we are able to encounter other people, or trees, or anything, beyond words, in silence.