According to a post on another blog, a document from 1967 shows that the Lutheran Church - Missouri Synod actually once commended the historical-critical method. The document, produced by the Synod's Commission on Theology and Church Relations, is entitled "A Lutheran Stance Toward Contemporary Biblical Studies." It can be found on the Synod's website here. Having read the document I am not convinced that it does support the historical-critical method, even if it acknowledges that certain aspects of it may provide helpful insights for the interpretive process. As one who studied for the ministry in the mid to late 80's and was instructed thoroughly in the historical-grammatical method, it was news to me that an official document of the Synod had been in existence then for 20 years that supported a methodology at variance with the way I was taught at a synodical school. To claim that it supports the historical-critical method undermines the continuity of the Synod's official convictions and proclamations on biblical studies over the last several decades. It also potentially legitimizes teaching against Synodical stances on such issues as women's ordination and evolution.
One of the arguments from the left is that the Synod was highjacked by hard-leaning conservatives who took the Synod in a direction different than it intended to go (see the recent article on the Daystar site by Domsch.) The usual culprits, of course, are the Preus brothers, J.A.O. and Robert who came from the ELS. It is true that many scholars from St. Louis were leading the church down a path different than where the Preus brothers were. The question, however, is whether those in St. Louis in the 60's and 70's reflected the true spirit of Missouri, or those who worked to correct what they perceived as a liberal course-change. Looking back to the roots of our church body which find their genesis in men who broke with the rationalism rampant in the church of their own time, I see the events preceding the Walk Out of 1974 as of a different spirit than what we find in our founding fathers.
Read the CTCR document for yourself and see if you believe it endorses the historical-critical method. The entire text is only eleven pages long and will only take a short time to read.