The 60s and the 70s were a rough time for the LCMS. We were embroiled in the "Battle for the Bible" - basically dealing with whether or not the Scriptures are, in fact, the Word of God. A lot of LCMS profs were saying, basically, no, it's not - at least not fully (yes, this is a gross simplification, but this is a blog post, not a doctoral thesis). And at that time the LCMS developed a new ally, someone with whom they had never allied before - the American Evangelical.
American Evangelicalism had long been one of the bigger foes of Lutheranism. They aren't sacramental - they think we are "too Catholic" - they lean to a lot of works righteousness - yaddy, yaddy ya. When the first "fundamentalists" came out in the late 19th Century - we didn't really want to be associated with them - not our circus, not our monkeys.
However, when we hit the battle for the Bible, our fundamentalistic Evangelical friends had lots of stuff on that topic - so we formed sort of a enemy of my enemy is my friend sort of thing. It was an issue of strange bedfellows - but for the time, it seemed to work.
I like that term "strange bedfellows" - because you know what happens when a couple shares a bed? Often, something new gets born. And the LCMS got infected with something new - the idea of trying to ape "Evangelical" styles of worship. By the 1980s you have a strong push to downplay the idea of liturigical worship -- let's just do it the Evangelical way. And all the worship wars since then sort of spill out of this.
The point is this: We saw a problem, and it was a serious problem... but in fighting that problem we picked our allies poorly, and we ended up picking up a lot of their baggage. It simply happens. If you read a bunch of folks because they are good on topic X, it's just going to happen that often their thoughts on topics Y and Z are going to creep in unless you stay incredibly vigilant.
So then - consider. We've got battles for today in the US. A lot of them seem to be social/moral issues. And we are getting a lot of partners for the fight for a more moral America.
... just remember what picking out strange bedfellows does.
I mean, sure, the guy's a Calvinist... and while his moral stance on topic X might be really good... remember the whole Crypto-Calvinist controversy and how much other junk is bad. (To say nothing of "Ask him about the Sacraments" - but I think that only applies to some Calvinsts)
I mean, sure, the guy's reformed... and while his moral stance on topic Y might be really good... how's his understanding of Christian obedience square with the Confessions? Or the two kingdoms?
I mean, sure, the guy's Roman Catholic... and while they've always been our allies on Z... what about their suppositions and approach to ethics is based not upon the Word but upon traditions and philosophy? Remember that Luther and the Reformation saw great danger in scholasticism, even though you find the scholastic useful on this point.
Fight the battles you need to now -- but remain Lutheran. Watch out for the leaven of the Pharisees... lest it corrupt you and you forget your first love.