IQ testing may not encompass all the traits that people consider to be 'intelligence' but it does a good job of picking out those that are capable of learning and making good decisions. Typically the top 1/6 of our population (IQ115+) make up the bulk of professional occupations. But only 2% of blacks score that high. Is it any wonder that top schools struggle to find qualified blacks to fill medical, law and engineering positions? They have to dip much further into the black cohort to reach acceptable numbers of students and it shows in black performance and graduation rates. If blacks had to have the same qualifications as whites and asians then a single school like MIT would use up virtually all of the high scoring black candidates. Instead elite schools take best that they can find, leaving 2nd tier schools with 3rd or 4th tier black students, and so on. Many or most black students find themselves in a school where their qualifications are at the bottom and their performance and graduation rate reflect that. This same scenerio is played out in many AA dominated jobs. AA gets blacks a job but their poor qualifications make it difficult to promote them or put them in positions of responsibility. Of course the blacks who truly were qualified find it difficult to escape the taint of low expectations given to other blacks. This scarcity of talent problem is the main reason why Africa is such a mess. With only a tiny portion of the sub-saharan population scoring as high as IQ100, there are few to fill professional and executive positions and jobs that are filled with IQ100 personnel here (like teachers, military officers, police) are filled with incompetents in Africa.