On the top of page 330, there is an error in the formula. Where there is (k - 3) there should be 1/(k - 3). Thanks are due to Oliver Lüdtke.
On page 335, the fifth line of the last paragraph, there is a missing word of "be." It should read be "would also be distinguishable." Thanks are due to Larry Kurdek.
For a paper that describes how correcting for stereotype accuracy can make a difference see Kenny, D. A., Snook, A., Boucher, E. M., Hancock, J. (2010). Interpersonal sensitivity and stereotype accuracy: Was Snodgrass right after all? Psychological Science, 21, 1735-1739.
A paper by Edwards (Edwards, J. R. (1995). Alternatives to difference scores as dependent variables in the study of congruence in organizational research. Organizational Behavior and Human Decision Processes, 64, 307-324. See also Griffin, D., Murray, S., & Gonzalez, R. (1999). Difference score correlations in relationship research: A conceptual primer. Personal Relationships, 6, 505-518.) describes a strategy to empirically select whether one should compute a discrepancy or difference score.
Readers might benefit by a paper by Mike Furr (Furr, R. M. (2010).The double-entry intraclass correlation as an index of profile similarity: Meaning, problems, and alternatives. Journal of Personality Assessment, 92, 1-15)
that describes dyadic indices. He suggests using the term "typicality" be used instead of "stereotype accuracy" and it does seem that researchers are using that term.