Picture this - a geneticist is on a show like Letterman with a studio audience.
Unknown to the geneticist, several volunteers give a DNA sample and fill out a questionnaire about personal characteristics (IQ, height, weight, age, how long did their parents live, sex, ethnic/race mix, education....).
Then the geneticist is given one of the DNA samples and a blank questionnaire and given 10 minutes for analysis of the sample. After this, the geneticist is to fill out the questionnaire with the answers that follow from the DNA sample, and then is to select that person from the crowd.
Could anyone do this consistently? How closely would the geneticist's answers match those of the subject? If this is somehow unfair, how is that?