Resolved: Most of the church is not Christian

In a discussion at TitusOneNine, I'm being politely asked, between the lines:  If I don't believe the church's teachings about the divinity of Jesus, the Trinity, etc., why am I intruding into the private club of those who do?  In response, I posed this proposition for debate, Oxford Union-style (I've edited it slightly here): 

RESOLVED:  No one may call himself a Christian if he demands more, as a condition of church membership, than doing one’s best to follow the Summary of the Law — Jesus (reportedly) said in Luke 10.25-37, do this and you will live, so to presume to require more than this would be to set one’s self above the Lord.

Another commenter responded: 

Disputed. ... Christianity is based on accepting Jesus as Lord and Savior and belonging to the community of faith—which includes belief in certain key precepts ....

Those who have come to believe those "key precepts" cannot be faulted for where their faculties and their consciences have led them. But I would disavow membership in any “community of faith” that went beyond this, insisting that its answers are the final ones and that those who don’t agree with the party line must either assent anyway or leave. Folks like that are like idolators, pridefully setting up their own conceptions above the reality that God has wrought.  (Hard experience has taught us that we don’t know everything about that reality, and that what we do “know” is necessarily provisional.) Fortunately, most of the Episcopal Church isn’t like that.