We recently had Casey Miller, one of the authors of the 2014 Nature article "A test that fails" (http://www.nature.com/naturejobs/scienc ... j7504-303a
), come visit our school and present about the biases in GRE scores. Like the plot in the linked article, there seems to be a lot of correlation between GRE scores and race/gender.
Dr. Miller flipped through various GRE scores, for GRE Q, GRE V, GRE AW, Physics GRE and all the other subject GREs too. In every single case, the relative scores of each of the race/gender groups were the same. That is, Asian-Americans and White Americans scored higher than other groups in every case. Men scored higher than women. I highly encourage inviting Dr. Miller to come speak at your department if you want to learn more.
This shows me that the scores are a better predictor of race/gender than they are for success. And the linked article that appeared today also shows how PGRE scores are not linked to success.
That said, some people are arguing for a complete removal of PGRE scores in admissions. Some are calling for an optional score report. I am leaning on the optional side because scoring high on the PGRE is still an achievement. And I take the side that your application package should be a way for you to show all the ways you are an excellent candidate. That is, admissions committees should be looking for evidence of excellence, not for signs of failure, so allowing someone who worked to score highly on the PGRE to submit their score would be in line with this. However, if the PGRE really is completely meaningless and if there is no meaning in a high PGRE score, then perhaps it makes sense to remove it completely.
I am very glad that the AAS made the statement it did. I hope AAS Council will approve this open letter at our society's meeting next month and change will begin to happen for the Fall 2017 admission year. I support what the draft open letter says (which is to encourage astronomy departments to make the GRE and PGRE optional or not required). At my school, my program already makes the PGRE optional (the wording is "strongly recommended" but it really is optional). I will be working with other students to make a case to changing this to "not required" to make it clear that it's optional.