Actually, I couldn't disagree more with the premise that astrology cannot be tested by statistical methods. The fundamental problem is that most people, and an unfortunately large number of "scientists", do not understand statistics, its methods, application and limitations. That, however, is a problem, with the audience, not with the techniques or the sciences that act in reliance thereon.
One of the most misunderstood limitations is that statistics applies, not to individuals, but to groups. Moreover, it is limited by the validity of the sampling universe used by the researcher. Astrology will be validated, if at all, only when we can demonstrate that it has mass application. If we can subsequently refine it to apply to individuals, then well and good.
One of the strongest areas where objective verification of astrological prediction may be found is in the arena of financial astrology. The activities of financial markets is one of large numbers of individuals acting in a common arena. People buy and sell tens of millions of shares of stocks each day. The number of businesses whose shares are traded number in the thousands. These sampling populations lend themselves eminently well to statistical analysis, and financial astrology may make predictions that are confirmed or refuted in very short order. The predictions of the better practitioners tend to be veified more often than not.
Medical astrology also lends itself to this technique. Unfortunately, privacy concerns and our tainted reputations often limit the research astrologer's access to this information.
I point to the Gauquelans' work as a hallmark of statistical astrological work, work that the practitioner ignores at his or her peril.
Finally, statistics is an established mathematical discipline. Its techniques are well established, and have been since the early eighteenth century when Gauss began to publish on the discipline. Research premised on statistics may be assessed, critiqued, defended and either confirmed or not, as the case may be, based upon well established and objective criteria. This is a big plus to any area of study that wants to confirm its legitimacy.
When all is said and done we must admit that serious research astrologers should master statistics, not avoid it If we chose to ignore it and other strict scientific methodology we merely justify the criticism of those who chose to dismiss us out of hand. We prove that we study a mere pseudo science. We remain a joke, an intellectual irrelevancy. Our study is capable of and deserves so much more.