"Mere" Christianity?

The idea of "mere Christianity" has gathered a lot of traction in the last decade or so. It's based on C.S. Lewis's book by the same title which extolled the virtues of essential Christianity. That which is foundational to the faith - the core in other words - should be that which is emphasized, the thinking goes. Any of that other "stuff" (like theological and practical distinctives and differences) should be de-emphasized or even ignored. All of this, of course, in the name of unity.

I've always thought there was something wrong with the "mere" movement. Someone else agrees with me - J. Todd Billings. In an article posted on the Christianity Today website, he writes, "Yet for many, fear of divisiveness has cut them off from the riches of the church's cloud of witnesses. Rather than providing a path to church unity, avoiding theological distinctives often just leads to superficiality."