Want to read more about how something good can "flip" into something divisive and legalistic? Check out my 2005 article in Plain Truth Magazine called "Never Trust a Skinny Person." And here's a place to get more info on Intuitive Eating. (I think this is a good approach, and seems grace-based, although the book and website is not "Christian.").
Do you have examples of other good ministries or efforts that can "flip" into splintering the church? Share them here!