In my opinion, Kaprow's main argument in this reading is that anything can be viewed as art even if it something that is done routinely and never seen as art. In this reading, Kaprow gives an example of something simple as brushing one's teeth. It was never seen as art until the details of the action was noticed.
This reading relates to the theme of the class by helping us look past what a "typical artwork" should be. It helps us realize that art can be performed in many ways and that everything that we are exposed to is basically art even if we don't actually notice it. Overall, this reading helps to think outside of the box when it comes to art and to utilize things that typically goes unnoticed as well.