The development of rich, reliable, and robust measures of the composition, structure, and stability of student thinking about core scientific ideas (such as natural selection) remains a complex challenge facing science educators. In their recent article (Nehm & Schonfeld 2008), the authors explored the strengths, weaknesses, and insights provided by a detailed exploration of three commonly used measures of student thinking about natural selection in a large sample of underrepresented minority students. One of their core findings was that all of the tools they studied--including the CINS--have strengths and weaknesses that must be carefully taken into consideration by those who employ, interpret, and act upon their outcomes. In this article, the authors offer their reply to Anderson, Fisher, and Smith's (AFS) (2010) article regarding the development and evaluation of the CINS. The authors view Anderson, Fisher, and Smith's defense of the CINS as sacrosanct to be antithetical to the spirit and reality of instrument development, evaluation, improvement.