I read this today, it refers to Barth, so it must be good!  It is also the best apologetic for practical theology I've ever seen (rather than the apologies for it that are all too frequently encountered).

Practical theology as worship

As we have seen, Practical theology and qualitative research combine to offer us a way of exploring the richness and complexity of creation. They move us beyond naive and simplistic assumptions about the world and human beings and allow us to explore the inner and often hidden depths of human experience.  Perceived in this way, we might describe this type of Practical Theology research as worship. It was Karl Barth who that the ultimate aim of all theology is worship (2002). Barth points towards the importance of doing theology with a spirit of praise and wonder; approaching the task as discovering the things of God with a deep sense of awe. As we seen in this book, theology does not relate only to the rational dimensions of human experience.  At a fundamental theology is always oriented towards the worship and praise of God. As we convert qualitative research and graft it into the service of theological action, it enables us to enter into some of the depths and complexities of creation; as we listen critically but openly to the voice it brings to us, we are drawn new understandings of and fresh perspectives on the divine drama. These new understandings should draw us into communion with God and inspire worship and praise at the intricacies and wonders of creation. It should not only us to understand, it should also enable us to love God and relate more closely to God, ourselves and to one another Matt. 22:3 7—40).

From Practical Theology and Qualitative Research, John Swinton and Harriet Mowat, London, SCM, 2006 Page 259

The Barth they refer to is Prayer Karl Barth, Louisville, Westminster John Knox Press, 2002