Who is a "qualified" social foundations teacher?

One of my (seemingly infinite) recent research interests is social foundations as a discipline -- what is it and what does it do? One of the points frequently made is that there are non-foundations faculty teaching foundations courses. That's generally thought of as bad. No one wants non-chemistry faculty teaching chemistry courses. One of the issues here, though, is the field has trouble defining itself, so it's difficult to determine who counts as a "qualified" social foundations faculty member and what counts as a social foundations class. If you have a Ph.D. in social foundations (that's what it says on my degree, anyway) and teach a course called "Social Foundations of Education" then that would count. But what about someone who has a degree in Reading with a research focus on reading and critical pedagogy and does other work on race/class/gender? If they teach a SoFo course, does that count? What if that same professor does not teach a social foundations course (perhaps one is not offered at her institution), yet teaches a reading course with a SoFo/critical pedagogy focus?

It could be that if we define SoFo broadly, then we are not doing as bad as we think we are. It also could be that if we define it that broadly, then it ceases to have meaning as a category.