Confessional,
No, I don't think it accurate to state that the LCMS wrote "new" liturgies; at least not in the sense that anything was created ex nihilo without reference to our previous tradition. We wrote new musical settings. We brought forward the tradition of the German Mass (Divine Service V). We used the Lutheran tradition of metrical paraphrases for the ordinary (Divine Service IV - which also relies heavily upon the Swedish 1531 Petri rite in the Eucharistia). We retained the Common Service (Divine Service III) and we retained the two revisions of the Divine Service that are deeply indebted to the liturgical renewal of the 20th century (Divine Services I, II). But if you look beneath the surface, you will discover the standard Western Mass. They share the same shaping, and at core that is a Preparation, Service of the Word (with introductory praise moving to reading of Scripture according to ancient precedent, with sermon and Creed, offering and hymnody), Service of the Sacrament (with Preface, Sanctus, Our Father, Verba, Pax, Agnus and Distribution, Post-communion canticle and collect, and Benediction). It sure doesn't take a liturgical scholar to realize that in all these we have the same liturgy (ordered action), utilitizing varied musical settings and both prose and rimed translations of the traditional texts.
Brian,
I am not sure how to respond as the subject seems ever to change.