As I came out of the Watchtower it was a real revelation to discover that "Christendom" was not nearly as divided as the WTBS would have us believe. The vast majority of Christians regard each other as fellow believers. They accept a number of core beliefs and consider everything else as a matter of personal choice. Even Catholics are regarded as faithful and well-meaning, even if a bit mislead.
I once read that most American Protestants picked the church they attend based on one of two things: 1) it was their parents church or 2) the building is easy to get to and they like the music. Doctrine simply isn't a major source of disagreement.