I have an MDiv from a Southern Baptist Seminary. We were taught the original languages, hermeneutics and exegesis. In theology, we were told about 4 end times scenerio, pick which one we thought was the right one, but be prepared to share with your congregation why you support it. Same for every other doctrinal subject. We were to start with Scripture, and back it up.
One of my big papers was on women in Ministry. Of course, the SBC do not allow women to be ordained. Although when I interview the head of the CSBC, he admitted there were women that had been ordained, and serving in ministry.
My paper was a huge defence of women in ministry. I got an A+, because I used Scripture, even if I totally disagree with the doctrine of the church. I could give you many more examples of people who preached against church doctrine, which were not disciplined.
As far as OSAS, I have believed that a long time after really searching the Bible. Yet I know others who didn't believe in OSAS, and we agreed to disagree.
You have obviously never been to seminary! My seminary had people from many denominations. Our professors were excellent and so was the library, spiritual formation, etc. We had people who were Anglican, Methodist, Mennonite, Lutheran, a few varieties of Baptists. And even some charismatics who took summer courses with us. No one was ever told to start with doctrine. We were told for every paper, every sermon, every Bible study to start with the Bible and show support. We also had some very interesting conversations during breaks & over lunch. One Reformed pastor was shocked when another pastor introduced himself as Reformed charismatic. A very interesting discussion, came out of that!
So the next time you start throwing around nonsense and misinformation like doctrine is first, I'm sure that might be true in some places. I'm working on a PhD in theology from an American theological institute. We also have people of many denominations. No one would ever dream of forcing doctrines on such a wide variety of people. As I studied theology my supervisor always had me read from a variety of sources that disagreed. I had to use my knowledge of the Bible to agree or disagree with many world renowned scholars. It always comes back to the Bible!