I think Kaprow was trying to imply that most everything we do in life is artistic in some form. We may not notice it at first, but if we pay attention to our actions we will start to realize some artistic values. When we do something everyday such as brushing our teeth, it just becomes routine and our minds really don't register every gesture we make. Not everything that is artistic is something you can find in a gallery. Art can be found anywhere.
I think this article can help improve our art by opening our minds and recognizing the artistic values in everyday things; not just paintings, drawings, photos, etc. There are a lot of artists who were shown in class who take everyday items, ideas, or methods and turn them into something artistic. We just have to be able recognize them.