As much as I agree this is a realist perspective on what most Christians actually do, I find both the underlying perspective and the fact that you'd support it really confusing here. If your book with instructions for living a moral life consists of a mixture of good and bad advice and you have to rely on a sense of moral intuition to avoid taking the bad advice, the book seems useless at best and actively harmful if you think it's possible for moral intuition to be wrong, since you aren't provided the tools for telling when you're off track and some of the advice being provided is pretty terrible and might not occur to someone who hasn't read the book. In practice it seems like a lot of people use that moral intuition to justify an underlying or instinctive bigotry. In an environment that encourages self-interrogation and growth they might challenge and dismantle those beliefs, but instead they are prevented from doing so because they're already being told that whatever they believe is automatically correct. It seems like a disservice to those people when you offer support for the latter.