It can cause us to grow in holiness. Sex doesn't have to be perfect or done in any particular way as long as it lies at the heart of a marriage. Knowing is doing, and our bodies do so much more for our soul than our thin intellects can. In the marriage bed, we are actually living the holiest bonds of the universe, maturing our first love, imitating God's own life. Holy, sacrificial lovemaking has the power to transcend scars and deepen our bonds like no catechism could ever do.
Real knowledge is bodily love and communion.
It is imagination that is touching and indwelling. It isn't dominated by the intellect and rationality. Imagine if we were to approach the marriage bed as intellectualistically as we approach our theology. We would kill the joy. You cannot analyze lovemaking without dispersing the delight.