Pr. Stuckwisch recently pointed out that the problem with "contemporary" worship is that it demonstrates a failure to trust in the Word of God. Ronald Feuerhahn addresses this problem in the final essay of the book, Through the Church the Song Goes On:
The fundamental problem [facing the church may be described] as a loss of faith--a loss of faith in the words and promises of God in His means of grace. We have come to a day in which there is no trust in those words and promises, but instead a compulsion to add something. Our Confessions call this the extra Christum--something added to Christ, "Christ plus something." That is a great evil in our midst.