This is poem is Knoebel’s most powerful use of simultaneity because he layers two stanzas of poetry in a perfectly synchronized fashion. One stanza is an abstract meditation on the presence, absence, and storage of thoughts while the other is pure imagery and embodied experience. The two are connected by being displayed and spoken through time, initially scrambling your thought process as it tries to follow two threads of text.
After your first reading of this short poem, I suggest you turn off the sound and read the visual text and then turn the sound back on and simply listen to the other stanza. Then experience them simultaneously again to see how meaningful the layering is, how the scheduling of the text leads you to re-imagine some of the sounds, and how the central metaphor brings the whole poem together.