This is from Hans Bader at the OpenMarket.org blog

Employers are often quite gullible about the claims made by ”diversity” trainers.   For example, they  permit minority trainers  to promote racial stereotypes that would provoke outrage if they were subsequently repeated by white managers or employees.   For example, Glenn Singleton, a wealthy ”diversity” trainer, teaches that ”white talk” is ”impersonal, intellectual, verbal” and ”task-oriented,” while ”color commentary” is ”emotional.” 

If a white person said this, it would rightly be regarded as a ridiculous, racist stereotype that relegates black people to inferior status.   But because Singleton himself is African-American, and he sugarcoats his  racist stereotypes about black people  by coupling  them with ideologically trendy attacks on white people (whom  he depicts as ”impersonal” and ”racist”), liberal school superintendents eat it up. [Diversity Training Backfires | OpenMarket.org]

This is correct—to the extent that such stereotypes are true, (and all stereotypes have some truth in them) Steve Sailer has been attacked for saying some of the same things Singleton is saying. However, Steve isn't trying to relegate   " black people to inferior status," but pointing out that different groups have different strengths. Glenn Singleton,[send him mail] by contrast, is trying say that blacks are superior.